Google indexing: what it is, why it matters and how to avoid problems

There are over 3 trillion web pages online, but according to the most reliable estimates, the Google index contains only a fraction of them, between 25 and 50 billion. In short, the search engine does not archive everything it finds, nor does it show every piece of content on its interface, but it selects the results to provide in response to user queries, drawing only from what it has decided to keep. Indexing is the very entrance to the immense and dynamic database that is the Google Index, a passage that is anything but automatic and sometimes not even guaranteed, that traces the boundary between what the search engine can (and wants to) find and everything that is ignored. A page can be online, searchable, even structurally correct, and yet remain invisible in search results if it is not indexed. Understanding if our content has really entered this system, identifying the technical or editorial obstacles that limit its visibility and intervening when something is excluded are all essential steps to transform online publication into an effective opportunity for traffic, growth and results. All this doesn’t only concern search engine optimization, but directly concerns the ability to be found, read and chosen.

What is indexing on Google

Indexing is the process through which a web page becomes part of the Google Index, which is the database that lists all the web pages known to the search engine.

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Then comes the crawling phase and this is when Google decides to record a piece of content, store it in its archives and make it suitable to be returned among the search results. It is not an automatic or guaranteed operation: publishing a page online, making it publicly accessible and even optimizing it according to SEO dictates is not enough if Google does not consider it indexable.

Indexing on Google is therefore the technical activity that precedes positioning and that simply specifies that a page has been taken into consideration, analyzed and memorized by the algorithmic systems of the search engine.

What indexing means in the digital context

The term “indexing” is not exclusive to the world of Google or SEO and there are other digital contexts in which this same term takes on different meanings.

For example, in computer science, economics and information science it is used to express a concept far from the context of Search. In particular, in database systems indexing is the process by which a reference structure is created to speed up queries. In this case, an index is a technical element that allows the database to retrieve data more efficiently, as happens with attribute indexes in relational systems.

In library science and digital archiving sciences, indexing means cataloging resources and documents according to standardized criteria: keywords, conceptual descriptors, tags. It is used to make content searchable within a closed system (archive or library system).

In statistical or macroeconomic terms, “indexing” can refer to the automatic adjustment of a monetary value based on a variable (for example, indexing wages to inflation).

Finally, in web publishing, the term indexing is sometimes improperly used to describe the manual insertion of a page in a directory or in an XML sitemap — confusing the concept of “reporting” with that of “effective inclusion” in a search system.

All these meanings share the principle of organizing, describing or connecting information, but they are clearly distinct from the specific concept of indexing as an internal process of Google Search architecture. For this reason, those who deal with content or SEO should always specify which “index” and which “system” they are talking about.

Operational and logical meaning of indexing on Google

Returning to our topic, for Google Search indexing means recording an analyzed and structured version of the page in its system, associating it with metadata, textual signals and algorithmic criteria that will allow it to be displayed in response to a query in the future.

To put it simply, we can say that Google compiles a huge private map of the web, omitting everything it considers irrelevant, duplicated, inaccessible or incomprehensible: what is deliberately excluded does not enter the Index and can never appear in the SERP.

In the specific language of Search, therefore, indexing a page means that it has been effectively included in Google’s Index, where information is stored on every piece of content that it has deemed valid, useful and readable for its system.

Another misunderstanding arises from the implicit overlap with other phases of online presence. Many confuse indexing with the simple fact that a page is visible on the browser, or associate it directly with positioning for a specific keyword. In reality, indexing is a well-defined technical step that takes place between discovery (crawling) and classification (ranking): it represents the official registration of a page in Google’s infrastructure, which from that moment can consider it for inclusion in the results, if and when it deems it appropriate.

To understand where indexing on Google fits in, it’s useful to remember the logical sequence used to evaluate a web page, a process that is divided into three distinct phases. The first is scanning or crawling, in which crawlers such as Googlebot actively search for new content or visit already known resources. The second is indexing, which is when Google examines the page, interprets its content and decides whether or not to include it in its Index. Only at a later stage can the page be evaluated to appear in search results based on its relevance to a particular query: this is the ranking.

Indexing is therefore an essential prerequisite but not sufficient to appear in search results. As also clarified in the official documentation, many pages are discovered but not indexed, or they may be indexed but not obtain concrete visibility due to lack of relevance, quality or compatible queries.

Indexing and positioning: differences and specifications

However, it is useful to reiterate and clarify the substantial difference between indexing and positioning on Google, two concepts that in speech (and sometimes even in written communications!) risk being confused and overlapping.

Indexing is an automatic operation that follows the scan performed by a crawler and determines the inclusion of the site in Google’s index. Positioning or ranking is the next step, so to speak, that is, the evaluation that Google’s algorithm makes of the site and its contents with respect to its parameters, which determines the position (in fact) in response to user queries.

An indexed page is “accessible” to Google, but not necessarily visible to users. Positioning — that is, the level of visibility that content manages to achieve in the SERP — depends on a further algorithmic evaluation. Google selects, from among the pages available in its Index, those that it considers most consistent with the intent of the search expressed by the user, and assigns them a position in the results page.

A common mistake is to associate the lack of display of a page with a ranking problem, when often the real cause is the absence of the page itself from the index: it has never been registered or it has been removed, perhaps following technical errors or negative evaluations. Without indexing, positioning cannot even be taken into consideration.

For this reason, those who work on the organic visibility of a site must necessarily start by checking the index and understanding the access status of their pages. SEO tactics, content optimization and link building only become relevant after the page has been accepted into the technical ecosystem of the search.

What is the Google index?

The Google index is the list that collects and stores information about the web pages that the search engine has decided to include in its results. It is not a static repository or a neutral inventory like the archive of a physical library, but a digital structure that constantly selects, reprocesses and updates the contents based on complex algorithmic criteria.

Every time a user performs a search, Google doesn’t query the entire web in real time, but instead searches its own index: this is where the structured data (text, media, metadata and signals) of the pages considered suitable are stored, and from this selected corpus the most relevant results are extracted and sorted.

To date, according to the most reliable estimates (including Siteefy, updated April 2023), the Google index exceeds 100,000,000 gigabytes in size and contains between 25 and 50 billion pages, while the total number of existing web pages could exceed 3 trillion. The figure speaks for itself: getting into the search results is not an automatic matter of online presence, but of selection.

Creating a website, opening a blog and publishing content online does not mean that all its pages will automatically and instantly appear in the search results, because the index only stores a part of the resources discovered during the crawling.

This is the meaning (in a nutshell) of indexing, the technical activity that precedes positioning and that simply specifies that a page has been considered, analyzed and stored by Google.

The dynamic archive of Search

Every page that enters this database undergoes a process of parsing and classification: the content is segmented, labeled, associated with topics, organizations, semantic coordinates, and becomes a unit that can be consulted by the system. But, above all, it is only kept if it falls within the criteria established by the engine — which balance usefulness, originality, technical integrity and relevance.

The index, therefore, is not a photograph of the web, but a reasoned map, reduced and oriented towards the purpose of providing a synthetically useful answer to every query. The very preservation of a page in the index is not permanent: allocation within this space is changeable, subject to revision, replacement or removal in the event that the page loses relevance, undergoes penalizing changes or is obscured.

The end user — user, marketing manager, SEO, editor — never sees the index, nor does he perceive the effects of it when content appears in Search or is ignored. But precisely because of its invisibility and its selective behavior, the index is the decisive element for visibility.

How it is updated and when it is reworked

The Google index is updated continuously, although we shouldn’t think of it as a single cycle or a scheduled system: the content is updated according to the signals received from the crawling systems, the algorithmic priorities and the frequency with which the resources are modified.

For each URL, Google builds a “trust history” that takes into account various parameters: how often the content has been modified, how regularly it is updated, how many interactions it has generated, how it is linked to entities and other nodes on the web. If a page is updated frequently but always offers similar or not very relevant information, it may not be re-crawled immediately. On the contrary, an informative site or an e-commerce site with significant updates can obtain quick recrawls to convey the changes more quickly.

The index is also reprocessed due to structural changes — migrations, redirects, changes in internal semantic relationships — or in the presence of problematic signals: 5xx errors, orphan pages, duplicate content.

A key fact to keep in mind: a page may already be indexed, but if it undergoes radical changes in structure, canonicalization or content, it could disappear temporarily from the index, be replaced by a duplicate or be reevaluated from scratch.

This dynamic can be monitored using the tools provided by Google Search Console, in particular the report on page indexing and the “URL inspection” tool, which shows whether the latest version of the page has already been absorbed or is still waiting to be reprocessed.

Selectivity of index entry

The data shown above reiterates a key concept: the default behavior of the search engine is very selective and only a part of the pages discovered are actually indexed.

The reasons for exclusion can be technical, structural or editorial.

Technically, a page can be blocked directly, through noindex, robots.txt or access errors (403, 404, server timeout). In these cases Google may even discover its existence, but deliberately excludes it.

However, most exclusions arise from a qualitative evaluation process: Google may correctly scan a page, not detect formal errors, but still decide not to include it in the index. This condition — explicitly reported in Search Console as “Crawled, but not currently indexed” — occurs in many cases and is often linked to content considered redundant, unoriginal, poorly informative or duplicated.

Google prioritizes what can “add value” to the index. If a piece of content replicates what has already been recorded by other sources, contains uninformative elements or has interpretability problems (such as Javascript that hides the body text), it can simply be discarded.

The type of site also has an influence: for very large sites, with thousands or millions of pages (catalogs, forums, dynamic archives), Google adopts a selective logic based on statistics. In these contexts, part of the architecture is indexed by test or by sample, and the rest is ignored until a signal emerges that justifies a deeper scan.

Index selection is therefore a form of algorithmic editing: a page is not included because it exists, but because it has the characteristics to serve the purpose of the search engine, i.e. to build a useful, efficient and up-to-date system of responses.

How indexing works

Once discovered and scanned, a web page is not automatically recorded in Google’s index: it is up to the search engine to decide whether that resource deserves to be kept, based on an evaluation that involves content, structure, technical signals and user experience.

The objective is not to archive everything that exists online, but to select only that which responds to certain standards of quality, coherence and usefulness. More than an exhaustive archive, in fact, the index represents for Google an operational tool based on a balance between representativeness, effectiveness and technical sustainability.

Inclusion only occurs if the page satisfies at least two criteria: it is accessible to (not blocked by technical errors or contrary instructions) and is considered useful with respect to the type of content it offers. Pages that are too similar to others already present, with thin content, poorly structured or with problematic signals can be ignored even in the absence of obvious errors.

To use a simile, indexing is like Google building a library, not of books but of websites and web pages: each word displayed on each indexed web page has a list entry, because an indexed page is added to the list entries for all the words it contains.

According to Google’s official guide, indexing “includes processing and analyzing text content and key content tags and attributes, such as title elements and ALT attributes, images, videos, and more”. Scanning processes are continuously running to keep up with the constant changes affecting the Web and other content, learning how often already scanned content is modified and scanning it if necessary. In this activity, they also discover new content as new links to these pages or information are displayed.

Again from a general point of view, Google emphasizes that it “never accepts payment to crawl a site more frequently”, as it provides “the same tools to all websites to ensure the best possible results” for all users.

How Google decides whether to index a page: content analysis and semantic signals

The content of a page is the first element evaluated during the indexing phase. In addition to text, Google also analyzes images, videos, structured data and semantic signals (titles, captions, contextual links, the correct hierarchy of headings) to understand the intent of the page, its relevance to specific topics and the consistency of the content with respect to its title or URL.

A short, generic resource or one that is too similar to others already present in the index is easily discarded because it is considered redundant; on the other hand, a well formatted page with original insights, a clear structure and consistent signals of theme and quality has a better chance of being memorized.

In particular, semantic signals (such as a descriptive title, a solid hierarchy of headings and the correct use of text attributes in images) help the algorithm to better interpret the page during the parsing and historicization phase.

Canonicalization and duplicate content

When Google detects similar content among multiple URLs, it automatically identifies a “canonical” version of the content, i.e. the one it considers the most representative and worthy of being indexed. All other versions are treated as duplicates and, as a rule, are not included in the index, unless there are precise HTML signals, such as rel=canonical, that explicitly indicate a preferred alternative.

This dynamic can cause misunderstandings: a page can be technically correct, accessible and well written, but if Google sees it as a duplicate of another (even from a different domain), it will choose not to index it.

In addition to URLs with identical content, other frequent cases of exclusion based on the duplication criterion include variations with parameters or query strings, poorly managed multilingual versions, e-commerce catalog paths and pages with dynamic filtering.

Canonical management therefore has a direct effect on this process: consistent use of the tag helps Google understand which variant should be saved in the index. On the contrary, the absence of explicit indications or an ambiguous URL structure can lead the search engine to prefer a different version from the one we intend to show users.

Code-side aspects that block indexing

Even if the content is well written, and the page is relevant to the context of the site, there are numerous technical barriers that can prevent it from being included in the index. The most frequent ones concern HTML instructions such as the noindex meta tag, inadvertently present or incorrectly configured during the implementation of publishing systems.

Indexing can also be blocked by server errors (500 and similar), blocks in the robots.txt file, multiple or incorrectly configured redirects, pages that require authentication to be viewed or that return HTTP statuses that are inconsistent with their actual availability.

One specific element should be noted in dynamic content generated via JavaScript: if the data appears in the browser but is not available in the source code returned to Googlebot, it is possible that the page will be interpreted as “contentless” and therefore ignored. In these cases, tools such as Search Console’s URL Inspection and “screenshoot rendering” become essential for diagnosing the real behavior of the engine.

Indexing, therefore, requires a constant balance between accessibility, informational value and technical integrity. When one of these elements is missing—even if only apparently—the page could be excluded, without any obvious formal error being reported.

How and when to request the indexing of a page

In the early years of Google, a page was included in the results almost exclusively in automatic form: the crawlers discovered new sites through links, followed them and, if valid, included them in the index.

Today, as mentioned, the behavior of bots is much more selective and oriented by structural signals, but the possibility remains — in some cases — to report to Google the presence or updating of a page, requesting a new access and indexing attempt.

This possibility is not equivalent to a guarantee: Google does not automatically index every page submitted, nor does it mechanically shorten the time. However, in the presence of newly published content, recently updated URLs or previously ignored pages, the request can serve as an impulse to reactivate the evaluation process. It is interesting to note that alternative search engines, such as Bing and Yandex, have launched the IndexNow system to manually submit a page for indexing, while Big G has preferred to maintain its “historical” line.

Manually submitting priority URLs or updating sitemap files are operations that express a clear intention on the part of the site owner: they declare that a given resource is ready to be taken into consideration again. For this reason, Google offers two main ways to “request” indexing: by directly submitting the URL using the appropriate tool in the Search Console, or by using an updated sitemap that highlights all the pages considered relevant. Both options are useful. But as with any algorithmic signal, it is the overall consistency of the page and the site that determines its real weight.

1. Sending a URL with the URL Inspection tool

The “URL Inspection” tool is available within the Google Search Console. This function is used to test and request the indexing of a specific page, as well as to obtain detailed information on the current status of the resource in the Google system. Once you have entered the URL in the search bar at the top, the tool checks if the page has been indexed, if it has scanning errors or if it contains instructions that prevent it from being registered.

If the URL is not present in the index (or is indexed but with visible problems), you can click on “Request Indexing” to send a direct request to acquire the page. After this report, the crawler schedules a new scan of the resource in the following days. It is not possible to know in advance when the crawling will take place or if indexing will be granted: it all depends on the qualitative evaluation of the resource and how it fits into the system’s priorities.

Requests for new indexing should, however, be used sparingly. Google does not publicly state the thresholds, but there are daily limits to the number of URLs that can be submitted manually. Furthermore, repeating the operation several times for the same page does not speed up the process or improve the chances of success. Instead, it is more useful to accompany the report with an actual revision of the contents or an improvement of the structure (for example, tag correction, better management of incoming links, semantic clarification).

2. Usefulness and management of sitemaps

The sitemap XML is the file that tells Google the technical structure of a site, indicating the complete list of URLs that you want to be indexed. Unlike the “URL Check” tool, designed for individual pages or specific situations, the sitemap is a systematic approach, suitable for the continuous management of the visibility of entire domains or sections.

The real function of the sitemap goes beyond mere “notification”: it is a direct source for Googlebot, a constant reference for exploring the information architecture of the site, validating its coverage, updating the status of already known pages. Each sitemap can and should contain not only the canonical URLs, but also the multilingual versions, the visual content (AMP pages, videos, images) and the relevant metadata — such as the date of last modification and any priorities.

The sitemap is always sent via Google Search Console, in the “Sitemaps” section: you just need to specify the path of the file within the domain, as long as the file itself respects the XML syntax established in Google’s guidelines. From that moment on, Google will manage the timing, frequency and priority of the scans.

Although sending the sitemap does not represent an absolute guarantee of indexing for each individual URL, it is one of the most effective ways to improve coverage and ensure that important pages are not ignored. It is particularly useful for complex sites, with many unconnected or automatically generated sections, to help Google navigate the entire perimeter of the project.

How to check if a page is indexed

Before even requesting indexing, it’s a good idea to check to see if a page has already been added to the index. The quickest way to do this is to use the command for advanced search site:, typed in the Google search bar, followed by the exact address of the page (e.g. site:mydomain.com/new-page). If the result appears, it means that the resource is indexed; if not, it may never have been indexed or may have been removed.

For a more reliable status, however, it is preferable to use the aforementioned “Check URL” tool in the Search Console.

Other signals that are more indirect — such as the absence of organic traffic, the impossibility of finding a page by searching for its main keywords, or the wording “crawled but not currently indexed” in the GSC report — may indicate a failure to include or the loss of indexing after a change, but require a more in-depth evaluation on a case-by-case basis.

We reiterate: this diagnostic component should never be overlaid with other concepts (visibility, positioning, crawling). Being absent from the index is a clear and binary condition, completely disconnected from the performance or perceived quality of the content.

Why some pages are not indexed

Access to the Index is the result of a rigorous selection process and, as a result, exclusions are much more common than you might think — and often they are not the result of explicit errors or malfunctions, but of algorithmic choices based on the perceived value of the resource.

A page that has been scanned but not indexed is not invisible to Googlebot: it is simply recognized but not considered useful, original or relevant for the index at that moment.

Understanding the reasons for this decision allows you to take targeted action, distinguishing between real technical problems, blocking signals and qualitative deficiencies. Exclusion from the index does not mean penalization, but lack of choice: and this is where the most effective SEO strategy is played out.

Technical errors, blocking signals and lack of connection

The reason for not being indexed can depend on both technical conditions that prevent access or evaluation, and the simple absence of useful links that facilitate its discovery. In both cases, the result is the same: the resource remains out of the index.

Technical reasons include intentional blocks and accidental issues. The former are the result of explicit instructions included in the page or in the site configuration: this is the case of noindex meta tags or rules imposed in the robots.txt file. Both solutions actively tell Google to ignore a resource. If used correctly, they are used to exclude non-strategic content (such as thank you pages, filters or duplicate versions), but if applied unintentionally or to resources that should be visible, they block the indexing process upstream.

In addition to technical blocks, there are also problems with the codes of HTTP status: pages that return error 404 (not found), 403 (access denied), 5xx (server error) or poorly managed redirects can cause Googlebot to abandon the scan. Even if the content exists, the crawler is unable to reach it or receives contradictory signals about the actual status of the resource.

Then there is a second, more subtle level of criticality, linked to the lack of internal connections or clear indications that allow Google to interpret the page as an integral part of the site’s architecture. Isolated resources have no inbound links and even the sitemap may not include them: this means that technically they can only be scanned if they are discovered by chance — through an external link, social sharing or an individual report.

In other cases, the page is well structured, accessible, error-free, but is classified by the same system as “scanned but not currently indexed”: a condition as seen reported in the Search Console which means, in practice, that the resource has been evaluated and deemed not suitable for the index.

The content has not been blocked. It has simply not been selected — often for reasons of quality, semantic repetitiveness or perceived low value. This is a physiological dynamic and is not directly related to errors. But it is always useful, in these cases, to critically re-examine the context: content, links, role within the site, specific signals provided to Googlebot.

How to improve the chances of indexing

Google can also find a page without ever deciding to index it, and to prevent this from happening it is necessary to put the content in the right conditions to be understood, positively evaluated and considered distinctive compared to what already exists in the index.

Improving the probability of indexing is not limited to sending the sitemap or making a manual request, but involves a series of combined measures: coherent semantic structure, logical links, correct HTML signals and metadata, stable technical performance.

For those who manage publishing sites, blogs, e-commerce or information projects, this means consciously designing each section according to its algorithmic exposure. Each element of the page — in form, content and its links to the site — contributes to the final decision made by the search engine.

Internal connections and semantic distribution

One of the most effective variables for indexing is the way in which a page is positioned within the structure of the site. Crawling and therefore indexing also occur by proximity: pages that are more “visible” to the eyes of the crawlers — because they are closer to the home page, connected by others already scanned or inserted in navigable paths — are more likely to be detected, evaluated and indexed.

A good strategy is to make each new page an explicit part of a thematic cluster already present on the site. Linking it from related content, from thematic hubs, from already positioned articles or from contextual menu items helps Google understand that the new element is part of a coherent system. The semantic relationship between pages is not only useful for the user, but becomes a concrete signal for the search engine: it communicates information density, complementarity and relevance.

Avoiding isolated structures, URLs that are too deep or paths without return allows you to keep the content in a navigable and accessible loop — not only for users, but also for the crawlers that determine the selection for the index.

Optimization of HTML structural signals

The quality of the code and HTML syntax also has a direct impact on indexing. The hierarchical headings <h1>, <h2>, <h3> must follow a clear logical order and respect the actual content dealt with on the page. The meta tags, starting from <title> and the meta description, provide Google with direct signals regarding the subject, tone and function of the page compared to other similar ones already present in the index.

A generic or redundant title — for example identical to that of 30 other pages on the site — reduces the chances that the document will be considered useful. Inconsistent or absent canonical tags can create confusion about inclusion priorities.

Furthermore, the consistent use of alt attributes for images, structured data (for example schema.org) and technical language declarations helps to make content more “readable” for the system.

These are not aesthetic measures: they are operational signals that feed the algorithmic evaluation of the content and its semantic relevance with respect to the starting index.

Selective management of exclusions and priorities

Not all pages need to be indexed, but all pages that we want to include in the system must avoid configurations that hinder their evaluation. Checking robots.txt file-side blocks and noindex instructions is an often-overlooked part of index optimization.

The point is not to “avoid using noindex”: it’s to use it where it’s needed. Some technical resources, intermediate pages, and content without SEO value deserve to be excluded. Others, on the other hand, can be blocked by mistake — for example during a migration, a test phase, or an automatic publication — and then remain permanently out of the index.

Similarly, blocking access to directories via robots.txt makes sense for redundant backend sections or documents, but completely prevents Google from accessing and evaluating the pages involved. If the content is useful, it should be kept accessible, or at least excluded with a noindex directive within the page itself.

Periodically checking these signals, verifying them with tools such as the Search Console URL Inspection and avoiding involuntary conflicts means creating a transparent environment for the engine: a site that doesn’t hinder, but clearly accompanies the path to the index.

What content and formats can Google index?

The Google index hosts content in different formats. Although it was created for textual HTML, the search engine has extended its interpretation capacity over time to include documents, media, structured files and even dynamically generated content.

Today, as we can read on this page, it can index the contents of most text files and some encoded document formats, and in particular file types such as:

• Adobe Portable Document Format (.pdf)
• Adobe PostScript (.ps)
• Comma Separated Values (CSV)
• Electronic Publishing (.epub)
• Google Earth (.kml, .kmz)
• GPS eXchange Format (.gpx)
• Hancom Hanword (.hwp)
• HTML (.htm, .html, other file extensions)
• Microsoft Excel (.xls, .xlsx)
• Microsoft PowerPoint (.ppt, .pptx)
• Microsoft Word (.doc, .docx)
• OpenOffice Presentation (.odp)
• OpenOffice Spreadsheet (.ods)
• OpenOffice Text (.odt)
• Rich Text Format (.rtf)
• Scalable Vector Graphics (.svg)
• TeX/LaTeX (.tex)
• Text (.txt, .text and other file extensions), including source code in the most common programming languages, such as:
  1. Basic source code (.bas)
  2. C/C++ source code (.c, .cc, .cpp, .cxx, .h, .hpp)
  3. C# source code (.cs)
  4. Java source code (.java)
  5. Perl source code (.pl)
  6. Python source code (.py)
• Wireless Markup Language (.wml, .wap)
• XML (.xml)

Google can also index the following multimedia formats:

• Image formats: BMP, GIF, JPEG, PNG, WebP, SVG and AVIF
• Video formats: 3GP, 3G2, ASF, AVI, DivX, M2V, M3U, M3U8, M4V, MKV, MOV, MP4, MPEG, OGV, QVT, RAM, RM, VOB, WebM, WMV and XAP

However, it isn’t enough for a file to be technically readable for it to be indexed: what counts above all is the context in which it is published, the way it is presented, and the signals it provides.

Differentiating between potential indexability and real visibility is fundamental for evaluating whether a site is working in the right direction in terms of content coverage.

Text files and structured documents

Google is designed to analyze mainly textual content. The HTML format is still the reference structure: easy to scan, readable, marked according to a clear semantic standard. HTML pages are the most directly compatible with index structures.

In addition to HTML, the engine is also able to read and potentially index other text document formats: PDF files, Word documents (.doc/.docx), Excel sheets (.xls/.xlsx), plain text files (.txt), .rtf pages and OpenDocument content. However, just because Google can read them doesn’t mean they will be displayed in the results: often these files are treated as complementary sources, with limited opportunity for organic positioning.

The logic of added information value also applies to these resources. A PDF without context, duplicated or disconnected from any informative section of the site is unlikely to be selected, regardless of its theoretical readability.

Finally, XML files (used for structured data, sitemaps, feeds) are not indexed as content in their own right, but are functional to the management of the index, representing a technical channel of communication between the site and the search engine.

Multimedia content: images, video, audio

Google can index multimedia content, but its presence in the results — and the way it is treated — follows a logic different from that applied to textual content. For example, images are not indexed “by themselves”: they are part of the context in which they are found. The alt attribute, the file name, the surrounding text and the structure of the page determine whether an image is recognized, classified and displayed among the results of Google Images.

In the case of videos, inclusion in the index requires the presence of specific metadata (through the VideoObject schema) and a page that also offers supporting textual content. Google does not work starting from the video file, but from the narrative and informative environment in which it is placed.

A video can only become visible in Search if it offers structured signals and is perceived as a useful autonomous resource. The use of a clearly identified thumbnail image, a clear description and a contextually themed page strengthens the link between video and search query.

Audio files (MP3, WAV and similar) can only be indexed in very specific conditions — for example, within podcasts officially supported by markup schema. Without an explicit content context, they remain accessory or secondary elements.

Dynamic content and JavaScript code

The adoption of modern frontend frameworks and the diffusion of content loaded via JavaScript requires special attention today for those who want to be indexed. Googlebot is able to read pages rendered via JS and even execute part of the code, but it does so through deferred—and not guaranteed—rendering.

In practice, if content appears only after an interaction or is generated with asynchronous calls (API, AJAX) and is not present in the initial DOM, its presence in Google’s eyes may be compromised. In these cases, the page may not be indexed, even if it is perfectly visible in the user’s browser.

The recommended solution in these scenarios is to adopt server-side rendering (SSR) techniques, use selective pre-rendering or make sure that the fundamental contents of the document are already available in the first response code. It is also useful to regularly test the pages with the URL Inspection tool (Search Console) and Chrome DevTools in “as Googlebot” mode to verify the content actually loaded.

From an indexing point of view, displaying all relevant information directly in the early stages of loading — in a stable, accessible and semantically labeled way — is now one of the decisive criteria for indexing dynamic content.

Even Google discourages the use of techniques that prevent access to content via JS, even when the site appears perfect to the user. In the absence of effective rendering or if key content is loaded after the initial page load, indexing may never occur or may occur only partially.

What is the purpose of indexing on Google and why is it important

Perhaps it goes without saying, but launching a website and not being on Google (we’re not talking about poor performance, but about being completely absent from the index) is like having a telephone line whose number nobody knows.

Indexing is in fact a prerequisite for obtaining organic traffic from Google: if we want our pages to be displayed in Search, they must first be indexed correctly – that is, Google must find and save these pages, inserting them in its Index, and then analyze their content and decide for which queries they could be relevant – and the more pages on the site that are included in this list, the greater the chance they will appear in the search results.

When all the steps are not correctly performed, the visibility of the site is practically nil and traffic drops drastically or is zeroed, because organic searches are responsible for more than 50% of all web traffic and almost 7 out of 10 browsing experiences start on Google or on another search engine.

Therefore, encountering errors and indexing problems can prevent the display of site pages in Google Search, and it is therefore crucial (to say the least) to know if Google can actually index our content and to know how to verify if the site is indexed correctly, using tools such as Google Search Console, which, with the Index Coverage Report, also provides useful information on the specific problem that prevented the site from being included in the list.

An unindexed site is practically invisible

Despite these steps forward, however, it can often happen that a page (or an entire site) is not found in the Search.

It is important to remember – and Google openly states this – that not all pages that Googlebot manages to find are actually indexed and added to the Google index: in some cases, as mentioned, this depends on the search engine’s evaluations, but in other situations it may be the result of a (more or less conscious) choice on the part of the site owners or managers.

In addition to tools to block crawlers from scanning and indexing, there can in fact be many potential problems with indexing, errors or complications that could prevent Google from correctly inserting web pages in its Index, and only by knowing them (or at least the main and most frequent ones) it is possible to learn the solutions to be implemented in order to regain visibility on the search engine and to avoid having precious pages not taken into consideration.

What are the errors that block indexing

So let’s focus on analyzing the situations that can prevent the visualization of pages and therefore cause serious damage to the site’s performance.

Usually, Google reports that the main causes that prevent indexing are server errors or 404 pages, website design that makes indexing difficult, rules that prevent inclusion in the index and the probable presence of pages with poor or duplicate or low-quality content.

But Tomek Rudzki went further and, as he explains in an article published on the Search Engine Journal, he analyzed and identified the most common indexing problems that prevent pages from being displayed in Google Search.

Thanks to his experience and daily activity of technical optimization of websites to make them more visible on Google, he has “access to several dozen websites in Google Search Console”; to obtain reliable statistics he therefore started by creating a sample of pages, combining data from two sources, namely already available client websites and anonymous data shared by other SEO professionals, involved through a survey on the former Twitter and direct contacts.

Rudzki describes the preliminary process to obtain valid information, and in particular how he excluded data from pages left out of indexing by choice – old URLs, articles that are no longer relevant, filter parameters in e-commerce and more – through the various ways available, “including the robots.txt file and the noindex tag”.

Then, the expert “removed from the sample the pages that met one of the following criteria”:

• Blocked by robots.txt.
• Marked as noindex.
• Redirected.
• Returning an HTTP error.

Furthermore, to further improve the quality of the sample, only pages included in the Sitemaps were considered, which are “the clearest representation of URLs of value from a given website”, even though “there are many websites that contain web site junk in their sitemaps, and some that even include the same URLs in their Sitemaps and robots.txt files”.

What are the main problems with site indexing

Thanks to sampling, Rudzki discovered that “the most common indexing problems vary according to the size of a website”. For his investigation, he divided the data into 4 size categories:

• Small size websites (up to 10,000 pages).
• Medium sized websites (from 10,000 to 100,000 pages).
• Large sized websites (up to one million pages).
• Huge websites (over 1 million pages).

Due to the differences in the size of the sampled sites, the author looked for a way to normalize the data, because “a particular problem encountered by a huge site could have greater weight than the problems that other smaller sites might have”. Therefore, it was necessary to examine “each site individually to sort out the indexing problems it is struggling with”, and then assign “points to indexing problems based on the number of pages affected by a given problem on a given site”.

This meticulous work then made it possible to identify the top 5 indexing problems encountered on websites of all sizes:

• Scanned – currently not indexed (quality issue).
• Duplicate content.
• Detected – currently not indexed (crawl budget/quality issue).
• Soft 404.
• Scanning issue.

Quality issues include pages with content that is thin, misleading or overly biased: if a page “does not provide unique and valuable content that Google wants to show to users, you will have difficulty getting it indexed (and you shouldn’t be surprised)”. Google may then recognize some of the pages as duplicate content, even if this was not intentionally intended.

A common problem is canonical tags pointing to different pages, with the result that the original page is not indexed; if there is duplicate content, “use the rel canonical or a 301 redirect” to ensure that “pages on your own site don’t compete with each other for views, clicks, and links”.

As we know, Google only allocates a certain amount of time to scanning each site, which we call the crawl budget: based on several factors, Googlebot will only scan a certain number of URLs on each website. This means that optimization is vital, because we mustn’t allow the bot to waste its time on pages that are of no interest to us and are not useful for our purposes.

404 errors indicate that “you have sent a page that does not exist or has been deleted for indexing”. Soft 404s display the “not found” information, but do not return the HTTP 404 status code to the server. Redirecting removed pages to other irrelevant pages is a common mistake, and multiple redirects can also be displayed as soft 404 errors: it is therefore important to shorten the redirect chains as much as possible.

Finally, there are many crawling problems, but probably the most important one is the issue with robots.txt: if Googlebot “finds a robots.txt file for your site but cannot access it, it will not crawl the site at all”.

Indexing, the main problems based on the different sizes of sites

After highlighting the main difficulties in general terms, the author also analyzed their causes, divided according to the size of the site examined.

1. Small websites (sample of 44 cases)

• Scanned, currently not indexed (quality problem or crawl budget).
• Duplicate content.
• Scanning budget problem.
• Soft 404.
• Scanning problem.

2. Medium websites (8 cases)

• Duplicate content.
• Discovered, not currently indexed (crawl budget / quality issue).
• Scanned, not currently indexed (quality issue).
• Soft 404 (quality issue).
• Scanning problem.

3. Large websites (9 sites)

• Scanned, not currently indexed (quality issue).
• Discovered, not currently indexed (crawl budget / quality issue).
• Duplicate content.
• Soft 404.
• Scanning issue.

4. Huge websites (9 sites)

• Scanned, not currently indexed (quality issue).
• Discovered, not currently indexed (crawl budget / quality issue).
• Duplicate content (duplicate, submitted URL not selected as canonical).
• Soft 404.
• Scanning problem.

Interestingly, according to these results, two categories of websites of different sizes – large and huge – suffer from the same problems: this “shows how difficult it is to maintain quality in the case of large sites”.

Other highlights from the study:

• Even relatively small websites (over 10 thousand pages) may not be fully indexed due to an insufficient crawl budget.
• The larger the website, the more pressing the problems of budget / quality of the scan become.
• The problem of duplicate content is serious, but its weight changes depending on the size of the site.

Orphan pages and URLs unknown to Google

During his research, Tomek Rudzki noticed that “there is another common problem that prevents pages from being indexed”, even if it doesn’t have the same quantitative impact as the ones described above. These are orphan pages, which are not linked to by other resources on the site: if Google doesn’t have a “path to find a page through your website, it might not find it at all”.

The solution is quite simple: add links from related pages or include the orphan page in the sitemap. Despite this, “many webmasters still fail to do so” and expose the site to more risky problems, concludes the author.

15 causes that block the presence of pages on Google

Indexing problems are therefore frequent and damaging, and thanks to another study, conducted by Brian Harnish on the Search Engine Journal, we can analyze a list of 15 causes that block the presence of pages in Search and hinder the success of our project, as well as discover possible solutions to the problems.

The first aspect to consider is that the time it takes for Google to index a site is not immediate and it can take days or even weeks before the search engine adds a resource to the list: therefore, before assuming there is a problem, it would be advisable to wait at least a week after sending a Sitemap or requesting indexing, and always check again after a week to see if any modified pages are still missing.

One possible reason why Google does not index a site is the absence of a domain name, which may be due to the fact that we are using the wrong URL for the content or to an incorrect setting on WordPress.

If this is what is happening, there are a few easy solutions: first, we can check whether or not the web address begins with “https://XXX.XXX…” – which means that someone could type in an IP address instead of a domain name and be redirected to the site – and then check that the IP address redirection is configured correctly.

One way to solve this problem is to add 301 redirects from the WWW versions of the pages to their respective domains and, basically, make sure you have a domain name.

A similar problem occurs if the site is indexed with a different domain or subdomain – for example, with http://example.com instead of http://www.example.com.

Problems with the quality of the content are another reason why pages are not included in Google, and are in fact the main reason why they are not indexed: we know that well written content is fundamental for success on Google, and therefore if we propose pages of poor quality that don’t even reach the level of the competition it’s difficult to imagine that the crawlers will take them into consideration.

It’s not about aspects related to SEO copywriting myths such as word count or keyword density, because 300-word content may not be indexed, but neither is content with a thousand words, but rather thin content and the usual concepts of quality and usefulness: that is, our pages must be good and informative, they must answer the user’s questions (implicit or explicit), provide information or have a point of view sufficiently different from other sites in the same niche.

A site that doesn’t pay much attention to the user isn’t even liked by Google

Having a user-friendly and engaging site is fundamental for good SEO, and consequently a site that is not easy to use and does not involve visitors (or, even worse, has a navigation system organized in complex link hierarchies that create frustration or exasperation) is an element that can cause indexing problems.

Google doesn’t want users to spend too much time on a page that takes forever to load, has confusing navigation or is simply difficult to use because there are too many distractions (such as above-the-fold ads or interstitial ads).

This is especially true for people using mobile devices, an area in which Google introduced the mobile-first index several years ago and where simple rules apply: it doesn’t matter how good the content is if the user using a smartphone or tablet can’t view it. Optimization for mobile devices is based on the addition of responsive design principles, and components such as fluid grids and CSS Media Queries can go a long way to ensure that users find what they need without encountering navigation problems.

Especially after the introduction of the Page Experience, loading time is an element that can determine exclusion from the Google Index and there can be several problems that affect the time needed to load pages. For example, there might be too much content on the page, making it difficult for a user’s browser to manage, or we might be using an outdated server with limited resources: in any case, what matters is ensuring fast loading.

Technical problems that can prevent inclusion in the Index

Let’s now look at some concrete examples of technical problems that can prevent pages and the site from being correctly analyzed by Googlebot for inclusion in the Index.

We’re talking about choices such as using a programming language that is too complex, both old and modern such as JavaScript, that has incorrect settings and causes scanning and indexing problems.

More specifically, the use of JavaScript to display content could cause negative situations: it is not a problem with this language itself, but rather with its application with techniques that can resemble cloaking or otherwise appear shady. For example, if we have rendered HTML and raw HTML, and a link in this raw HTML that is not present in the rendered one, Google may not scan or index that link; so, as Harnish says, “don’t hide your JS and CSS files even if you like to do it”, because “Google has said it wants to see all your JS and CSS files when scanning”.

The same difficulty in seeing the page in the SERP is found when using plug-ins that prevent Googlebot from crawling the site: the US expert mentions robots.txt, which can be automatically set to noindex for the whole site, making it impossible for Googlebot to crawl.

Obviously, the robots.txt file itself can also be a critical element and it is advisable to follow best practices to try to avoid or limit errors, thinking carefully about which parts of the site we want to avoid scanning and therefore use the disallow accordingly on these unimportant sections. Basically, a good technical SEO strategy can prevent this type of indexing error, as well as helping pages to have good parameters in Core Web Vitals and in other aspects that can affect Google’s ability to analyze pages and deem them worthy of its Index.

Other aspects that can affect page indexing

Managing technical SEO also allows you to avoid falling into situations that can cause problems for the proper functioning of the site, such as incorrect settings of meta robots tags (such as involuntary and unwanted settings on noindex, nofollow) or redirect loops.

Chains of redirects, in particular, can also result from typing errors when writing the URL, which create a duplicate address that points to itself; to identify and resolve these cases, in WordPress we can find the file .htaccess and search for the list of redirects, verifying that everything is in order (and possibly setting the redirects 302 to 301).

It is also important to submit a sitemap to Google, which is perhaps the best method to make the search engine discover the pages of the site and to increase the chances that each page will be scanned and indexed correctly. Without a sitemap, Googlebot will randomly and blindly stumble across our pages, unless they are already indexed and receive traffic; moreover, it is not enough to send the map only once (especially for dynamic sites), but it is necessary to update and periodically send the file for scanning and indexing important pages and new content.

One last element that can determine the failure to index the pages of the site is to be found in the history of the domain itself and, specifically, in the possible presence of previous and incorrect manual actions. Google has repeatedly stated that penalties can come back to haunt us and if we don’t correctly execute the reconsideration process to clean up the site, it’s highly probable that even new resources won’t find space in the Index. This also applies to domains purchased recently, which could have a dark history of penalties from Google – which is why it is essential to first check the site’s “criminal record” before investing, because it can then take precious time to make Google understand that there is a new owner who has cut ties with the past.

What are the 15 reasons for indexing problems on Google

To summarize visually before concluding, the 15 potential causes of indexing problems on Google are:

1. Waiting time
2. Absence of domain name
3. Indexing with a different domain
4. Poor quality content
5. Poor user experience
6. Non-mobile-friendly site
7. Slow loading pages
8. Complex programming languages
9. Improper use of JavaScript
10. Plugins that block Googlebot
11. Blocks in the robots.txt file
12. Settings in the robots meta tags
13. Redirect chains
14. Sitemaps not sent
15. Sanctioned domain with unresolved manual actions

We therefore understand that there are many elements to evaluate if we find our pages absent from Google Search, a real mischief that risks nullifying all SEO efforts because, in fact, it considerably reduces our visibility and the opportunity to reach the public.

Therefore, in addition to dedicating time to content, technical SEO and link management (fundamental components to allow the site and its pages to reach the quality and authority necessary to compete on the search engine), we must not neglect indexing, the first step in our race to the first page.

The evolution of Google indexing

The way in which Google builds its index has not remained unchanged over time. In the initial versions, each page was treated as an atomic entity and the primary purpose was to collect textual information to be displayed on desktops, while today the index is modeled on a logic of dynamic selection: it evaluates the mobile experience, extracts only relevant blocks and decides whether to keep an entire page or just some parts.

Originally, Google’s index was strongly anchored to the desktop version of the Web and applied the same editorial model of the nineties to Search: a static page, with visible text, links, and a linear structure. The parallel introduction of multimedia content, dynamic layouts, complex semantic structures and, more recently, app environments and conversational AI has redesigned the criteria for access and prioritization.

In particular, AI Overview functionalities and differential rendering by device and query are transforming the index into an adaptive structure, where it’s not just about being included, but also about how content is interpreted. Communicating effectively with this new system requires awareness of its priorities and the (implicit) signals it uses.

From desktop viewing to mobile-first indexing

The original structure of Google’s index was strongly anchored to the desktop environment: Googlebot scanned and evaluated versions of pages designed to be displayed on large screens, with complex content and articulated navigation. This approach, effective for years, showed its limits when access from mobile devices became prevalent.

In 2016, Google introduced the concept of “mobile-first indexing”, which was formally completed in 2023: today the index is mainly built from the mobile version of a page. Content that is only visible on desktop, or that is dynamically loaded on mobile in a non-accessible way (for example, textual content hidden behind interactions, such as expandable tabs or drop-downs, or asynchronous interfaces that cannot be indexed), risks not being considered at all.

This change has had direct implications not only on readability, but on the entire SEO ecosystem: the structure of the pages, the management of links, the content visible in the mobile viewport and the natively loaded markup become discriminating factors.

In this model, the index is no longer built on a “complete” view of what the site can offer, but on a reduced, minimal and mobile-centric representation that favors the most common user experience. Ignoring this parameter means compromising the indexing process from the start, even in the presence of valid content.

AI Overview and generative summary: impacts on the index

With the launch of AI Overview, Search has introduced a new type of response: synthetic, structured, automatically constructed by combining extracts from multiple sources in the index thanks to generative AI. The aim is to provide useful and direct content from the first scroll of the SERP, reducing the number of clicks needed for the user to obtain information.

This evolution doesn’t change the existence of the index, but transforms its function. Today a page can be included in the system, but no longer queried “in its entirety” when a user performs a search: what matters is the portion of content deemed relevant, fragments that can be retrieved, rewritten, mixed with others, and automatically displayed as part of a generated response.

This introduces a change of perspective also for those who produce content: presence in the index is a necessary condition, but no longer sufficient to obtain direct visibility. To emerge in the current form of Search, a text must not only be useful, but formulated in a clear, interpretable and extractable way.

Today, elements such as well-exposed definitions, list structures, readable formats, explicit statements and verticalized content increase the likelihood that Google will select parts of the content to feed its AI-driven responses.

Selective indexing and flexible architectures

Today’s index is not a neutral collection of URLs, but an adaptive structure that continuously models itself according to the perceived value, the search intent and the marginal utility of the resources already present. This means that Google not only chooses whether to include content, but also which part to keep active, update or actually show.

The logic is differential: sections that are updated frequently are scanned more often, redundant portions are skipped, and resources that are very similar to pages already present are ignored for efficiency. In many cases, Google can only partially memorize documents — selecting the most informative sections — or index them with low priority, reserving the right to extend their treatment only in case of further signals (links, navigational research, performance).

In light of these dynamics, it becomes fundamental to think of content not only as a “page to be included in the index”, but as an information block with an effective weight. Each visible portion (paragraphs, graphics, definitions) must have a reason to exist on its own.

Indexing is not a static photograph, but a process with variable density: Google keeps what it considers useful, and leaves aside what it considers marginal. Editorial adaptation to this reality is, to all intents and purposes, a new form of optimization.

Google indexing: FAQs and questions to be clarified

Although indexing is a precise and technically defined phase in the functioning of Search, many of the questions that arise from those who manage online content concern its mechanisms: how can you tell if a page is indexed, why does some content not appear, what to do when creating a new resource, or what happens if it is updated.

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In this section we collect the most frequently asked questions from webmasters, digital entrepreneurs, content editors and marketing professionals. The answers are organized in a concise but complete form, with the aim of clarifying common doubts and helping to correctly interpret the tools and signals provided by Google.

1. What does it mean to index a website on Google?

It means that at least one page of the site has been added to the Google index: that is, it has been scanned, analyzed and considered suitable to appear in the Search results.

1. How can you check if a page is indexed?

You can use the site:URL command in the Google Search bar (e.g. site:example.com/page), which will show you an immediate confirmation. For a more precise analysis, it’s better to use the Search Console’s URL Inspection tool, which also provides details on the date of the last scan and any critical issues.

2. How long does it take to index new content?

There is no predetermined timeframe. New pages published on sites already known to Google can be indexed in a few hours, while less linked or potentially redundant resources can take days or weeks. Requesting indexing through Search Console speeds up the scan, but does not guarantee registration in the system.

3. Why doesn’t a site appear on Google even though it has been active for some time?

There can be several reasons: no sitemap, no URL reporting, technical errors or simply unavailability due to a lack of external or internal links. Even correctly published pages can be scanned but excluded for qualitative evaluations.

4. What does the status “scanned but not currently indexed” indicate?

This message indicates that the page has been visited by Googlebot, but the content has not been included in the index. This generally happens when the system does not detect sufficient information value, finds redundancies or does not receive additional signals that justify its inclusion.

5. Is it possible to manually report a URL to Google?

Yes. Using Search Console, you can use the URL Inspection tool to request the indexing of a single page. This function is particularly recommended in the case of new content or important updates to a page already published.

6. Is there any accessible content that Google decides not to index?

Yes. Even publicly accessible content can be excluded if it is considered not very useful, duplicated, too similar to other already known content, or if it is not included in a clear informative context. The index favors pages that are actually relevant and structured.

7. Can duplicate content still be included in the index?

Only in specific cases. If Google identifies the page as the canonical version or if it doesn’t find any better alternatives, content that is similar to other content can be kept. Generally, however, it selects only one variant for each duplicate content.

8. What is the difference between noindex and blocking via robots.txt?

Noindex is an instruction that allows Google to scan the page but prevents it from being stored in the index. Blocking via robots.txt, on the other hand, prevents the crawler from accessing the resource at all: in that case Google won’t even be able to see the page’s content.

9. What is the relationship between indexing and positioning?

Indexing is the prerequisite: without a page present in the index, no ranking is possible. Only indexed pages can be evaluated to appear in the SERP, and only among these does Google select — based on ranking — which ones to show in response to queries.

10. Does an indexed page automatically appear in the results?

No. The index contains billions of pages, but only a selection is shown in each SERP. Inclusion depends on relevance, quality, competition for the query and algorithmic signals. A piece of content can be indexed and not appear for specific searches, or not generate visible traffic.

11. What actions can promote faster indexing?

Effective strategies include structuring the site correctly (clear and consistent internal links), sending updated sitemaps, avoiding duplicate content and improving HTML signals (title, description, canonical tag). It is also essential to make sure that the pages are not blocked by noindex or robots.txt.