What the rule says
"Use a maximum of [number] characters as a textual snippet for this search result. (Note that a URL may appear as multiple search results within a search results page.) This does not affect image or video previews. This applies to all forms of search results (such as Google web search, Google Images, Discover, Assistant, AI Overviews, AI Mode) and will also limit how much of the content may be used as a direct input for AI Overviews and AI Mode."
Three things sit in there that people set the rule without knowing.
It is text only. Image and video previews are explicitly untouched, so a low number does not give you a plain result. Those have their own rules.
It reaches the AI surfaces. Together with nosnippet, this is one of only two rules on the page that name AI Overviews and AI Mode, and the only one that limits AI use by degree rather than switching it off. Whether a character cap on the snippet translates into a proportional cap on what a model receives is not something the documentation quantifies, and not something you can observe from your side.
One URL can appear more than once. The cap is per result, and the parenthesis is Google's own warning that a page may show up several times on one results page.
The two values that change what the rule is
| Value | What it does |
|---|---|
0 | No snippet is to be shown. The documentation calls this "Equivalent to nosnippet" |
-1 | Google chooses the length it believes most effective for discovery |
| any number | Cap of that many characters on the text snippet |
| unparseable | The rule is ignored entirely |
The first row is the one that catches teams. A template that renders max-snippet:0 from an empty configuration field has not set a mild limit. It has set the strongest snippet rule Google offers, with the AI consequences that come with nosnippet, and nothing in the markup says so.
The last row is the quieter version of the same problem.
"This rule is ignored if no parseable [number] is specified."
There is no error, no fallback to a safe default, and no signal in Search Console. A typo, a templating variable that rendered empty, a value with a stray unit: the rule silently does not exist, and the page behaves exactly as if you had never written it. Since the visible outcome of "no rule" is a normal snippet, the failure looks like Google ignoring you rather than like a bug in your own markup.
Structured data walks past it
The documentation is unusually explicit that this rule does not govern rich results:
"You can limit the length of a text preview with max-snippet, but that robots meta tag doesn't apply when the information is provided using structured data for rich results."
There is one exception, and it runs the other way. Among all the robots rules, max-snippet is the one that does reach into structured data, for description fields only:
"Robots meta tag limitations don't affect the use of that structured data, with the exception of article.description and the description values for structured data specified for other creative works. To specify the maximum length of a preview based on these description values, use the max-snippet rule."
So if your concern is the length of a description pulled from schema.org, this is the instrument. If your concern is a recipe carousel or a review star, it is not, and no robots rule is. Google's advice there is to change the structured data itself.
The same carve-out appears once more, and it is worth reading closely because it applies to both max-snippet and max-image-preview:
"However, this limit does not apply in cases where a publisher has separately granted permission for use of content. For instance, if the publisher supplies content in the form of in-page structured data or has a license agreement with Google, this setting does not interrupt those more specific permitted uses."
A limit that does not apply where permission was granted elsewhere is a limit with a door in it. Most sites publish structured data without thinking of it as permission, and that is precisely what it is here.
When it meets another rule
"In the case of conflicting robots rules, the more restrictive rule applies. For example, if a page has both max-snippet:50 and nosnippet rules, the nosnippet rule will apply."
Worth stating plainly because template systems produce exactly this combination: a site-wide nosnippet from one plugin and a per-page max-snippet from another. The per-page rule loses, and it loses quietly.
What to do with it
Treat 0 as a different rule. Guard against it being produced by an empty field, and review anywhere it already is.
Validate the rendered value, not the template. Look at the HTML Google receives. An unparseable number leaves no trace anywhere else.
Do not use it to control rich results. Change the structured data instead.
Do not expect it to clean up the result. Images and video previews are untouched. Those need max-image-preview and max-video-preview.
Be honest about the AI effect. The documentation says the rule limits how much content may be used as a direct input. It does not say how much, and you cannot measure it.
Source
- Google Search Central, "Robots meta tag, data-nosnippet, and X-Robots-Tag specifications" (retrieved 3 September 2026, page dated "Last updated 2026-03-24 UTC"): https://developers.google.com/search/docs/crawling-indexing/robots-meta-tag. Source of every passage quoted here: the max-snippet definition including the AI clause and the permission carve-out, the sentence on unparseable values, the special values 0 and -1, the conflicting-rules paragraph, and both passages from the structured data section.
- That this rule and
nosnippetare the only two carrying the AI clause was checked rather than assumed: "AI Overviews" occurs four times on the page, two inside each of those two definitions and none elsewhere, counted in the retrieved text with "snippet" (45 occurrences) as a control term confirming the retrieval was intact.
Frequently asked questions
Does max-snippet count characters or words?
Characters. The documentation defines the number as a maximum of that many characters used as a textual snippet.
What happens if the value is not a number?
The rule is ignored. Google states this outright, and there is no warning anywhere that it happened.
Is max-snippet:0 the same as nosnippet?
The documentation describes the value 0 as "Equivalent to nosnippet", so it carries the same consequences, including for AI Overviews and AI Mode.
Will it shorten a rich result from my structured data?
Only for description values such as article.description. For other rich result content, the robots meta tag does not apply and the structured data itself has to change.