Knowledge base v2.13.0 · Community edition · data through 2 October 2026
Topic · Publisher controls
John Mueller's answer to his own quiz was that robots meta tags can make a page more visible: his closing slide recommended max-snippet:-1 and max-image-preview:large, the latter mattering mainly in Discover. The nosnippet rule removes the text snippet and video preview but not the title, max-snippet caps the snippet length in characters (0 equals nosnippet), and data-nosnippet hides one passage, such as a phone number, but works on few elements, can spill over the rest of the page if the HTML is broken, and should not be toggled with JavaScript. Day 2 extends Day 1's opt-out discussion: Google's documentation says nosnippet keeps a page's content out of AI Overviews and AI Mode as direct input, max-snippet limits how much they may use and a page must be eligible for a snippet to be a supporting link, and Mueller said Google builds those answers from snippets. Two points from the talk go beyond the docs, which say only that Google chooses the length: max-snippet:-1 can give a longer snippet than no rule, and a limit too short to be useful may mean no snippet at all. The max-video-preview rule caps previews in seconds and notranslate stops Google offering a translated result; Mueller said a notranslate meta tag named google also switches off Chrome's translation, which Chromium's Translate design document supports and a 2008 Search Central post documents for Google Translate, though Google Search's current documentation does not mention it. Day 3 showed the parts of a text result, attribution, title link, snippet and site name, which Google generates from its understanding of the page even when the owner provides nothing. Google estimated that a snippet or title change takes 1-2 days on average and up to several weeks or months, because the page must first be recrawled and reprocessed; its title link guide says a few days to a few weeks. On Day 2 Gary Illyes repeated that max-image-preview:large can make content do surprisingly well in Discover, and a community speaker said search engines ignore HTML tags written inside a meta description (said at the event).
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John Mueller opened with a true-or-false quiz slide asking whether robots meta tags can make a page more visible in Search results than having none, and later answered that the statement is true.
“You can use robots meta tags to be more visible in Search results than without robots meta tags.”
Wording checked against the slide or recording
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence slide photo, transcript
Used byrequirement DEV-IDX-04
The nosnippet rule stops Google from showing a text snippet or video preview for a page in search results, while the page's title is still shown.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence slide photo, transcript
Used byrequirement DEV-IDX-05glossary term nosnippet and data-nosnippet
The nosnippet rule also prevents a page's content from being used as a direct input for AI Overviews and AI Mode in Search.
“Also prevents the content from being used as a direct input for AI Overviews and AI Mode in Search results.”
Wording checked against the slide or recording
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence slide photo, transcript
Used byrequirement DEV-IDX-05glossary term nosnippet and data-nosnippet
The max-snippet:[number] rule limits a page's search result snippet to that number of characters (100 characters, for example), and max-snippet:0 shows no snippet, the same as nosnippet.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence slide photo, transcript
Used byrequirement DEV-IDX-04glossary term max-snippet
max-snippet:-1 removes the length limit and can produce a longer snippet than having no rule, because by default Google keeps snippets to a length it considers reasonable instead of quoting a page at length.
“max-snippet:-1 = No limit. (can be more than without)”
Wording checked against the slide or recording
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence slide photo, transcript
The max-image-preview rule sets the maximum size of a page's image previews: none shows no preview, standard a default-sized one and large the largest possible, for example in Discover.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence slide photo, transcript
Used byrequirement DEV-IDX-04glossary term max-image-preview
The max-video-preview rule sets the maximum number of seconds of a video preview in Search; 0 allows only a static image and -1 means no time limit.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence slide photo, transcript
Used byrequirement DEV-VID-05
To be as visible as possible in Google, John Mueller's closing slide recommended the robots rules max-image-preview:large and max-snippet:-1.
“To be as visible as possible in Google, use: max-image-preview:large, max-snippet:-1”
Wording checked against the slide or recording
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence slide photo, video, transcript
Used byrequirement DEV-IDX-04
John Mueller said Google uses the snippet as a way of building AI Overviews and AI Mode answers, so if a page forbids a snippet, Google cannot use that snippet for them.
“we use the snippet as a way of building out the AI Overviews and the AI Mode answers”
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
Used byrequirement DEV-IDX-05
John Mueller said data-nosnippet is rarely needed but lets a site keep a specific piece of text, such as a business phone number, out of the snippet, so the page can still be found for it while searchers have to visit the page to see it.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
Used byrequirement DEV-IDX-07glossary term nosnippet and data-nosnippet
The data-nosnippet attribute can be used on only a handful of HTML elements.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
Used byrequirement DEV-IDX-07
Broken HTML can widen data-nosnippet: if a div marked data-nosnippet is not closed properly, the rest of the page can be blocked from the snippet as well.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
Used byrequirements DEV-HTM-05, DEV-IDX-07
John Mueller said valid HTML is technically not a ranking factor but does matter for controls such as data-nosnippet.
“valid HTML is technically not an SEO ranking factor, but it does play a role”
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
Used byrequirements DEV-HTM-05, DEV-IDX-07
John Mueller said, hedging with 'I think', that the max-snippet limit also applies to AI Overviews and AI Mode.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
A max-snippet value too short for a useful snippet may lead Google to show no snippet at all, John Mueller said.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
Used byrequirement DEV-IDX-05
John Mueller said Google Search does not always show an image thumbnail for a result, and when it does, the thumbnail is usually limited to the size of the result entry.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
max-image-preview:large matters mainly in Discover, where it allows a large image that draws people's attention, so the rule can make a page more visible than leaving it out, John Mueller said.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
John Mueller said he thinks setting max-video-preview to -1 will not make Google show an hour-long video preview in search results.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
Used byrequirement DEV-VID-05
John Mueller speculated that the use of max-video-preview may change in future, for example in Discover, where letting people view a full video could make sense.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
The notranslate robots rule tells Google not to offer a translation of the page in search results.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
Used byrequirement DEV-IDX-09
John Mueller said notranslate can also be set in a meta tag named google, and that in that form it also turns off Chrome's automatic translation of the page.
Speaker John MuellerIn Day 2, 10:30 · Controlling indexingEvidence transcript
Used byrequirement DEV-IDX-09
Search engines such as Google and Bing would ignore HTML tags written inside a meta description, a community speaker said.
Speaker Sören BendigIn Day 2, 10:40 · Lightning session D: Rendering and JavaScriptEvidence transcript
Used byrequirement DEV-HTM-03
Setting the max-image-preview robots meta tag to large can make content perform surprisingly well in Discover, Gary Illyes said.
Speaker Gary IllyesIn Day 2, 13:50 · Using images to your advantage and Engaging Search users with videosEvidence transcript
Used byrequirement DEV-IDX-04
The snippet shown for a web result is reconstructed from the tokens stored in Google's index: Google knows the position of each token in the document and rebuilds the snippet from those positions.
“the snippet that you see was reconstructed from these tokens”
Speaker GoogleIn Day 2, 16:15 · How does the index look like?Evidence transcript
Google's robots meta tag specification says that with nosnippet a static image thumbnail, if available, may still be shown when that results in a better user experience.
Publisher Google Search CentralAnnotates Day 2, 10:30 · Controlling indexing
Google's AI features guide says a page must be indexed and eligible to be shown in Google Search with a snippet to appear as a supporting link in AI Overviews or AI Mode, with no additional technical requirements.
Publisher Google Search CentralAnnotates Day 2, 10:30 · Controlling indexing
Used byrequirements DEV-AIF-01, DEV-IDX-05glossary term AI Overviews
Google's robots meta tag specification says data-nosnippet may be extracted both before and after rendering, so the attribute should not be added to or removed from existing elements with JavaScript.
Publisher Google Search CentralAnnotates Day 2, 10:30 · Controlling indexing
Used byrequirements DEV-IDX-07, DEV-REN-05
Google's robots meta tag specification says Google chooses the snippet length when no max-snippet rule is set, and with max-snippet:-1 chooses the length it believes most effective; it does not say that -1 produces longer snippets.
Publisher Google Search CentralAnnotates Day 2, 10:30 · Controlling indexing
Used byrequirement DEV-IDX-04
Google's Search documentation gives notranslate as a rule for a robots or googlebot meta tag or an X-Robots-Tag header, and says the rule opts a page out of all translation features in Google Search.
Publisher Google Search CentralAnnotates Day 2, 10:30 · Controlling indexing
Used byrequirements DEV-IDX-03, DEV-IDX-09glossary term X-Robots-Tag
Google's snippet documentation says snippets are created automatically, primarily from the page content, to preview the part that best relates to the user's specific search, so one page can get different snippets for different searches; sometimes the meta description is used instead.
Publisher Google Search CentralAnnotates Day 2, 16:15 · How does the index look like?
Used byrequirement DEV-HTM-03
Google's robots meta tag specification says the nosnippet rule also prevents a page's content from being used as a direct input for AI Overviews and AI Mode, and max-snippet also limits how much of it may be used that way.
Publisher Google Search CentralAnnotates Day 2, 16:15 · How does the index look like?
Used byrequirement DEV-IDX-05glossary term max-snippet
Before adding nosnippet or a low max-snippet value, weigh the cost in AI features: both limit how much of the page AI Overviews and AI Mode can use, and John Mueller described those answers as built from snippets.
Author Ibrahim AnjroAnnotates Day 2, 10:30 · Controlling indexing
To hide one detail, such as a phone number, a price or a direct answer, instead of the whole snippet, wrap it in data-nosnippet on a span, div or section in the server HTML and validate the HTML so that an unclosed element cannot hide the rest of the page from snippets.
Author Ibrahim AnjroAnnotates Day 2, 10:30 · Controlling indexing
Used byrequirement DEV-IDX-07
International sites should remove notranslate from their templates unless translation must be prevented: the robots or googlebot form switches off Google Search's translation features, and John Mueller said the form named google also blocks Chrome's translation for visitors who do not read the language.
Author Ibrahim AnjroAnnotates Day 2, 10:30 · Controlling indexing
Used byrequirement DEV-IDX-09
Set max-snippet:-1 and max-image-preview:large on every indexable template unless licensing requires otherwise, and check that no CMS, plug-in or CDN setting adds lower snippet or image preview limits by default.
Author Ibrahim AnjroAnnotates Day 2, 10:30 · Controlling indexing
Used byrequirement DEV-IDX-04
Treat nosnippet, data-nosnippet and max-snippet as AI visibility settings too: Google lists them as the controls for content in AI features, and if AI answers are built from index snippets, as Google said on stage, a blocked or shortened snippet leaves AI Overviews and AI Mode less to use.
Author Ibrahim AnjroAnnotates Day 2, 16:15 · How does the index look like?
Google estimated that a snippet update takes 1-2 days on average and up to several weeks to months, because the page has to be reprocessed to extract the new text.
Speaker Gary IllyesIn Day 3, 15:45 · How long does it take to..?Evidence slide photo, transcript
Google estimated that a title update takes as long as a snippet update: 1-2 days on average, up to several weeks to months.
Speaker Gary IllyesIn Day 3, 15:45 · How long does it take to..?Evidence slide photo, transcript
Used byrequirements DEV-HTM-03, DEV-MON-10
A text result on Google's results page is made of parts such as the attribution, the title link, the snippet and the site name.
Speaker Gary IllyesIn Day 3, 13:25 · How Search results are bornEvidence transcript
Google generates the parts of a text result, such as title link and snippet, from its understanding of the underlying web page, even when the site owner provides nothing extra.
Speaker Gary IllyesIn Day 3, 13:25 · How Search results are bornEvidence transcript
Used byrequirement DEV-HTM-03
Google's title link guide says Google has to recrawl and reprocess a page to notice changes to the sources of its title link, which may take a few days to a few weeks.
Publisher Google Search CentralAnnotates Day 3, 15:45 · How long does it take to..?
Used byrequirements DEV-HTM-03, DEV-MON-10
After changing a title or meta description, wait at least a few days before judging the result in Search; if nothing changes after several weeks, check that the page was recrawled, since snippets and titles are only re-extracted from a reprocessed page.
Author Ibrahim AnjroAnnotates Day 3, 15:45 · How long does it take to..?
The nosnippet rule also prevents a page's content from being used as a direct input for AI Overviews and AI Mode in Search.
Lead-generation, local-service and e-commerce sites should normally stay included, because AI answers cite and link sources. Sites selling paywalled or licensed content should test exclusion on a child property first. Use nosnippet only if you also want out of regular snippets.
John Mueller said Google uses the snippet as a way of building AI Overviews and AI Mode answers, so if a page forbids a snippet, Google cannot use that snippet for them.
AI Mode and AI Overviews use the same crawling and the same index as Search. At serving they add grounding on the Search index and query fan-out.
Google's AI features guide says a page must be indexed and eligible to be shown in Google Search with a snippet to appear as a supporting link in AI Overviews or AI Mode, with no additional technical requirements.
AI Mode and AI Overviews use the same crawling and the same index as Search. At serving they add grounding on the Search index and query fan-out.
Google said that when AI Overviews or AI Mode run a query fan-out, the generated queries are sent to Google's Search index and documents come back with their snippets, which then feed the AI-generated answer (part of this passage is unclear in the recording).
John Mueller said Google uses the snippet as a way of building AI Overviews and AI Mode answers, so if a page forbids a snippet, Google cannot use that snippet for them.
Search engines such as Google and Bing would ignore HTML tags written inside a meta description, a community speaker said.
One site that builds its whole content by rendering also rendered its meta description with HTML tags inside it, which makes no sense and points to a flawed process.
Google's Discover slide recommended large images at least 1,200 px wide, with more than 300,000 total pixels and a 16x9 aspect ratio, enabled by the max-image-preview:large setting.
max-image-preview:large matters mainly in Discover, where it allows a large image that draws people's attention, so the rule can make a page more visible than leaving it out, John Mueller said.
Google generates the parts of a text result, such as title link and snippet, from its understanding of the underlying web page, even when the site owner provides nothing extra.
The snippet shown for a web result is reconstructed from the tokens stored in Google's index: Google knows the position of each token in the document and rebuilds the snippet from those positions.
Setting the max-image-preview robots meta tag to large can make content perform surprisingly well in Discover, Gary Illyes said.
max-image-preview:large matters mainly in Discover, where it allows a large image that draws people's attention, so the rule can make a page more visible than leaving it out, John Mueller said.
Google's Discover slide recommended large images at least 1,200 px wide, with more than 300,000 total pixels and a 16x9 aspect ratio, enabled by the max-image-preview:large setting.
Setting the max-image-preview robots meta tag to large can make content perform surprisingly well in Discover, Gary Illyes said.
Allow full snippets and large previews with max-snippet:-1 and max-image-preview:large
Rests on 8 claims, 7 of them in this topic
Do not add nosnippet or a short max-snippet unless you accept losing snippets and AI feature use
Rests on 6 claims, 6 of them in this topic
Use data-nosnippet on a span, div or section to keep one detail out of snippets
Rests on 6 claims, 6 of them in this topic
Give every indexable page a unique, descriptive title element in the server HTML
Rests on 7 claims, 5 of them in this topic
Rests on 8 claims, 4 of them in this topic
Write valid HTML and close every element
Rests on 4 claims, 2 of them in this topic
Plan releases and fixes around Google's processing times, and judge results only after them
Rests on 11 claims, 2 of them in this topic
Allow video previews with max-video-preview:-1
Rests on 2 claims, 2 of them in this topic
Keep pages indexable and snippet-eligible, the whole technical requirement for AI features
Rests on 5 claims, 1 of them in this topic
Send robots rules for PDFs, images and other non-HTML files in the X-Robots-Tag header
Rests on 3 claims, 1 of them in this topic
Do not add, change or remove robots meta tags with JavaScript
Rests on 9 claims, 1 of them in this topic