Review Schema
Review schema is the schema.org markup (Review and AggregateRating) you add to a page so a star rating, a review count, and the thing being rated are stated as explicit data rather than left for a machine to infer from prose. It helps a crawler or a model read your reviews correctly. It does not, on its own, make you more likely to get cited by an AI assistant.
Why it matters
Written out as text, a rating is ambiguous: "rated 4.7 out of 5 by our customers" requires a reader, human or machine, to trust the sentence. AggregateRating turns that into a typed field with a ratingValue, a reviewCount, and an itemReviewed. That precision is genuinely useful for eligibility into rich results (the starred listings you sometimes see in Google), and it makes the number unambiguous to any system parsing the page. What it is not is a confirmed, independent factor in whether an AI assistant chooses to cite you. Google's own guidance on optimizing for AI features states plainly that no special markup or schema is required for AI Overviews or AI Mode, and warns against writing content specifically "for AI." Treat review schema as good data hygiene, not a citation lever.
How it works
You implement it as JSON-LD, a script block in the page's source that visitors never see. Two shapes cover most cases: a single Review (author, review body, a reviewRating) or an AggregateRating (ratingValue and reviewCount rolled up across many reviews). Either one needs an itemReviewed, the product, business, or article the rating actually belongs to, or it has nothing to attach to. The scale matters too: Google assumes 1 to 5 unless you declare bestRating and worstRating explicitly. Validate with Google's Rich Results Test before you ship it; it will flag missing required fields immediately.
Common mistakes
The serious violation is fabricating or self-assigning a rating, or marking one up that visitors can't actually see on the page. Google's guidelines explicitly forbid both, and there are real manual-action consequences for review markup that doesn't correspond to visible content. A subtler mistake is publishing an AggregateRating with no reviewCount attached, which reads as unverifiable and is often ignored. Letting the schema drift from reality is just as common: the page shows 12 reviews, the markup still claims 500 from a year ago. Keep the two in sync every time reviews change, and don't treat the schema as a one-time setup task.
Relation to AI visibility
It's tempting to assume structured markup is the thing that gets you cited by ChatGPT or Perplexity. The evidence doesn't support that. Google has said no special schema is required for its AI features, and separately, an Ahrefs analysis of roughly 75,000 brands found that how often a brand is mentioned across the web correlates with AI citation rate at about 0.664, roughly three times stronger than the correlation for backlinks (about 0.218). In other words, being talked about, in reviews on third-party sites, in comparison posts, in forums, moves the needle more than markup does. Review schema still earns its place: it makes your own rating unambiguous to anything reading the page, and it's a prerequisite for rich results in classic search. Just don't mistake it for the primary lever on AI citation. That lever is being mentioned, accurately and often, elsewhere.
Example
Take a small tax firm in Leipzig with a page of client testimonials rendered only as styled text and star icons. A developer adds AggregateRating markup: itemReviewed set to the firm, ratingValue 4.6, reviewCount 41, scale declared as 1 to 5. Google's Rich Results Test now validates it cleanly, and the listing becomes eligible for a starred snippet. That's the honest scope of the change: the firm's own site now states its rating unambiguously. Whether an AI assistant recommends the firm when someone asks "who handles freelancer taxes in Leipzig" still depends far more on whether the firm is mentioned, favorably, on review sites, forums, and local directories the model has actually seen.
Common questions
Can I mark up my own company with review schema?
Only with reviews that are real and visible to visitors on the page. Google's guidelines prohibit self-authored or invented ratings, and mismatched markup can trigger a manual action.
Does review schema help me get cited by ChatGPT or Perplexity?
Not directly. Google states no special schema is required for its AI features, and it isn't a confirmed independent citation factor for other AI engines either. Ahrefs data shows brand mention frequency correlates with AI citation far more strongly than markup does.