Knowledge base v2.13.0 · Community edition · data through 2 October 2026
Thing · Concept
The part of a page that serves its purpose, which Google identifies and weighs more than boilerplate such as navigation.
Glossary · Main content (centerpiece)
The part of a page that serves its purpose, as opposed to header, navigation and footer: any part that directly helps the page achieve its purpose, including images, video, tools and user-generated content. Google identifies it and treats it as the most important part of the page.
Google's sitemap guide says Google uses lastmod only when it is consistently and verifiably accurate, and counts a change to the main content, the structured data or the links of a page as significant, but not a changed copyright date.
Google Search Central · Day 2 · Welcome to indexing day!
Google's canonicalization guide says that when Google indexes a page it determines the page's primary content, which it also calls the centerpiece, and clusters pages whose primary content is the same or very similar.
Google Search Central · Day 2 · Understanding what's on a page
Google's Search Quality Rater Guidelines define main content as any part of the page that directly helps it achieve its purpose, including text, images, videos, page features such as calculators and content created by users, and they count the title at the top of the page as part of it.
Google Search Quality Rater Guidelines (PDF, 11 September 2025) · Day 2 · Understanding what's on a page
Google's Search Quality Rater Guidelines say navigation links are a common type of supplementary content, and that content behind tabs and user reviews or comments may count as main content on some pages and as supplementary content on others, depending on the page's purpose.
Google Search Quality Rater Guidelines (PDF, 11 September 2025) · Day 2 · Understanding what's on a page
Google's hreflang guide says pages that translate only the template (navigation, footer) around main content in one language still count as duplicates, because localized versions are duplicates only if the main content stays untranslated; it recommends hreflang for such pages.
Google Search Central · Day 2 · Focusing on Internationalisation and Localisation
Slide and stage claims that name it, the ones Google’s documentation does not cover first.
Gary Illyes said not everything on a page can or should be important: if everything were placed in the main content, nothing would stand out as main content, which he called working as intended.
Gary Illyes · Day 2 · Understanding what's on a page
When tokenizing for Search, Google attaches metadata to each token for use in ranking, such as whether the word appeared in the header or in the main content (tagged 'centerpiece' on the slide), in bold or in a heading; Gary Illyes said he was not showing all of the metadata.
Gary Illyes · Day 2 · Understanding what's on a page
For soft 404 detection, the position of error text decides: an error in a less important part such as the navigation need not make a page a soft 404, but an error message alone in the main content, like 'Error establishing a database connection', does, much as a human would judge it.
Gary Illyes · Day 2 · Understanding what's on a page
Google's soft 404 detection tells the page chrome, such as navigation and footer, apart from the main content by analysing the page's visual hierarchy alongside its text.
Gary Illyes · Day 2 · Understanding what's on a page
Google's systems sometimes fail to determine a page's main content correctly, and structured data helps because site owners tend to mark up what is actually important rather than boilerplate or ads.
Day 2 · What is Structured Data and why we need it on the internet.
A community speaker advised keeping headings inside the main content in a logical hierarchy (title, section subtitles, subsections) so agents can follow its structure, avoiding several H1 elements and skipped levels such as an H3 followed directly by an H5.
Carlos Ortega · Day 1 · Lightning session A: Automation and AI
Google extracts every element of a page so that it can tell the header, the navigation and the main content apart, and a slide labelled the main content as very important.
When the JavaScript is not accessible to Googlebot, Google cannot render the client-side DOM that the page builds asynchronously, so parts of the page may be present while the main content is absent.
Erin Sparling · Day 2 · What is Google friendly JavaScript
A Google slide labelled the parts of an example blog page, marking the header and the navigation as not so important and the main content as very important.
Gary Illyes · Day 2 · Understanding what's on a page
Gary Illyes pointed to Google's Search Quality Rater Guidelines as the detailed source on how Google thinks about the main content of a page.
Gary Illyes · Day 2 · Understanding what's on a page
On Google's example blog page, the post title and opening sentence counted as important because they sit in the main content, in front of the user, while the site tagline, the 'Categories' sidebar and category links such as 'Hugo (7)' counted as less important supplementary text.
Gary Illyes · Day 2 · Understanding what's on a page
To make a word count for ranking a page, Gary Illyes said the simplest step is to move it into the main content, because where text sits on a page already contributes quite a bit to ranking.
Gary Illyes · Day 2 · Understanding what's on a page
A comment section below a blog post can still be part of the page's main content and can contribute to Google's understanding of the page.
Gary Illyes · Day 2 · Understanding what's on a page
A page's main content includes all of its headings and its visible title.
Gary Illyes · Day 2 · Understanding what's on a page
Gary Illyes said the main content is what Google considers when ranking a page.
Gary Illyes · Day 2 · Understanding what's on a page
Gary Illyes defined a page's main content as any part of the page that directly helps the page achieve its purpose, what it was built for.
Gary Illyes · Day 2 · Understanding what's on a page
Main content is not only text: images, videos, a tool or anything else that helps a page achieve its purpose can be main content.
Gary Illyes · Day 2 · Understanding what's on a page
Content created by other users can be main content: on a user-generated content site, the user-generated content can be the page's main content.
Gary Illyes · Day 2 · Understanding what's on a page
Content inside tabs, for example separate tabs for a product description and a manufacturer description, might be part of a page's main content.
Gary Illyes · Day 2 · Understanding what's on a page
Pages whose boilerplate, such as menu and footer, is translated while the main content is not are near matches: the main reason to visit is the same, so Google clusters them as duplicates.
Make the main content of every template easy to separate from the header, navigation and footer, for example as one clearly delimited main area, because Google identifies the main content and treats it as the most important part of the page.
Ibrahim Anjro · Day 2 · How is HTML interpreted
For pages people are likely to ask an AI assistant about (product, pricing, documentation and policy pages), server-render the main content so a live, user-triggered read does not depend on client-side JavaScript finishing quickly.
Ibrahim Anjro · Day 2 · Lightning session D: Rendering and JavaScript
Check rendering per template rather than per URL: inspect one URL of each page type (product, category, article) in URL Inspection and confirm that the main content, prices and internal links appear in the rendered HTML.
Ibrahim Anjro · Day 2 · Lightning session D: Rendering and JavaScript
Wrap permission-based features (location, payments, camera) and WebGL effects in feature detection with a fallback, so the main content renders when the API is missing or the permission is declined; never make indexable content wait for a permission prompt.
Ibrahim Anjro · Day 2 · What is Google friendly JavaScript
Check robots.txt for Disallow rules covering JavaScript bundles, build folders or API endpoints the page calls while rendering, including on separate API or CDN hostnames with their own robots.txt, then confirm in URL Inspection's live test that the rendered HTML contains the main content.
Ibrahim Anjro · Day 2 · What is Google friendly JavaScript
With a headless CMS, choose the rendering per template before launch (server-rendered or pre-rendered for pages that must rank), and make any agent-built test suite assert that the main content and <a href> links are present in the rendered HTML.
Ibrahim Anjro · Day 2 · What is Google friendly JavaScript
Put the terms a page should rank for in its main content (title, headings, opening paragraphs) rather than only in sidebars, tag lists or footers; footer keyword blocks are unlikely to add ranking value.
Ibrahim Anjro · Day 2 · Understanding what's on a page
Return real error status codes for error states, 404 or 410 for missing content and 503 for outages such as a failed database connection, also in single-page apps; a 200 page whose main content is only an error message is treated as a soft 404 even when header and navigation look normal.
Ibrahim Anjro · Day 2 · Understanding what's on a page
Make location and variant pages differ in their main content (local stock, staff, prices, addresses) and return 404 for empty or invalid combinations; otherwise every URL that fits the pattern can be folded into one canonical.
Ibrahim Anjro · Day 2 · Handling web duplication
Give each important video its own watch page where the video is the main content, add VideoObject markup and list the video in a video sitemap; a video buried in a long article lacks the dedicated watch page that Google listed as a key factor.
Ibrahim Anjro · Day 2 · Using images to your advantage and Engaging Search users with videos
Kit items about Main content: their own words name it, or several of the claims they rest on do.
Wrap each page's primary content in one clearly delimited main area
Rests on 14 claims, 12 of them naming Main content; its own words name Main content
Place the words a page should rank for in its main content, not in footers or sidebars
Rests on 5 claims, 3 of them naming Main content; its own words name Main content
Never serve error states, empty results or failed data loads with a 200 status
Rests on 10 claims, 2 of them naming Main content; its own words name Main content
Make each page's language unambiguous by translating the template with the main content
Rests on 12 claims, 2 of them naming Main content; its own words name Main content
Make pages that share a URL pattern differ in their main content
Rests on 6 claims, 1 of them naming Main content; its own words name Main content
Use real heading, title and emphasis elements instead of styling alone
Rests on 2 claims, 1 of them naming Main content; its own words name Main content
Server-render the main content and everything indexing depends on (SSR, static generation or hybrid)
Rests on 11 claims, 1 of them naming Main content; its own words name Main content
Describe only the page's main product in Product markup, not related-product carousels
Rests on 4 claims, 1 of them naming Main content; its own words name Main content
Keep each HTML response well under 2 MB and put the main content and JSON-LD early
Rests on 2 claims, 0 of them naming Main content; its own words name Main content
Also inglossary terms Main content (centerpiece), Content quality (effort, originality, talent or skill, accuracy)
Things named in the same claim, with the number of claims they share.