Review and aggregate-rating structured data
Review structured data (the schema.org review and aggregate-rating types) can produce review star snippets in search results when attached to a supported item such as a Product, Recipe, or Book. Google enforces strict policies: ratings must come from genuine reviews, self-serving reviews of your own business are not eligible, and only certain schema types support the snippet. This page explains correct usage and the rules.
What this means
Review structured data describes a single review (the review type) or an aggregate of reviews (the aggregate-rating type, which carries a star value plus a count of how many reviews) of a thing. Attached to a supported host item, it can produce a star-rating snippet in search.
The rating must come from real reviews and reflect what the page shows. Review markup is not a standalone type for a snippet — it must be nested on a supported item type.
Supported types and the self-serving rule
Review snippets are supported only on specific schema types Google lists — for example Product, Recipe, Book, Movie, Course, SoftwareApplication, and a few others — not on arbitrary pages. Putting review markup on an unsupported type will not yield a snippet.
Critically, Google does not allow self-serving reviews: ratings about your own business or organization placed on your own site are not eligible for the snippet. Ratings must be genuinely sourced, and fabricated values violate the policies and can cause manual action.
- Only supported host types (Product, Recipe, Book, etc.) qualify
- Aggregate rating uses a star value plus a count of reviews
- Self-serving reviews of your own business are not eligible
- Fabricated ratings violate Google policy
Validation
Validate with the Rich Results Test (eligibility) and the Schema Markup Validator (schema.org conformance), and monitor Search Console's Review snippets report for errors and policy warnings. Ensure the star value is within the stated best-rating scale and that the reviewed item is present on the page.
Because review snippets are policy-sensitive, treat eligibility conservatively: only mark up genuine reviews of supported items, never inflate counts, and accept that Google still decides whether to display stars.
How it appears in analytics and logs
Review and aggregate-rating markup supplies a star value and a count of reviews for a reviewed item. It can show a star snippet only on supported host types and only when ratings are genuine. Self-serving reviews about your own organization, or fabricated ratings, are not eligible and can trigger manual action.
Diagnostic use case
Add review or aggregate-rating markup that is eligible for star snippets while staying within Google's self-serving review and supported-type policies.
What WebmasterID can help detect
WebmasterID confirms which crawlers fetch the reviewed page and the response. The hard rule against fabricated star ratings and review counts aligns with WebmasterID's own policy of never inventing ratings; validation of the markup uses Google's tools.
Common mistakes
- Adding self-serving reviews of your own organization and expecting a star snippet.
- Fabricating a star value or review count, which violates Google policy.
- Attaching review markup to an unsupported schema type.
- Marking up ratings that do not match reviews visible on the page.
Privacy and accuracy notes
Review markup describes published reviews and aggregate ratings, not private visitor data. WebmasterID records crawler fetches of the page as bot events and never fabricates ratings or collects reviewer identity.
Frequently asked questions
- Why are my review stars not showing in search?
- Common reasons: the host type is not supported for review snippets, the reviews are self-serving (about your own business), the markup has errors, or Google simply chose not to display them. Eligibility never guarantees the snippet.
- Can I add aggregate ratings to my homepage about my company?
- No. Google treats reviews of your own business on your own site as self-serving and ineligible for the review snippet. Ratings must come from genuine reviews on a supported item type.
Related pages
- Product structured data
Product structured data uses schema.org Product with a nested Offer and optionally aggregate-rating and review data to describe items for sale, enabling product rich results such as price, availability, and review snippets. This page covers required and recommended fields, Google's policies on review data, and how to validate the markup with the Rich Results Test and Search Console.
- Diagnosing structured data errors
Structured data (schema.org markup, usually as JSON-LD) lets search engines understand a page and can make it eligible for rich results. Errors — missing required properties, invalid types or values, markup that does not match visible content, or policy violations — can make a page ineligible for those features. Diagnosis uses validators and Search Console's rich-result reports.
- Article structured data
Article structured data (Article, NewsArticle, BlogPosting from schema.org) marks up news, blog, and editorial pages so Google can better understand and present them, including in features like Top stories. This page covers the type choice, the properties Google recommends (headline, image, dates, author), and how to validate the markup with the Rich Results Test and Search Console.
- WebmasterID docs
How WebmasterID records crawler activity without inventing ratings.
Sources and verification notes
- Google Search Central — Review snippet structured dataSupported types, self-serving policy, and required fields.
- schema.org — aggregate-rating type
Last reviewed 2026-06-24. Facts are checked against primary/official sources where available; uncertain specifics are marked “Data not yet verified” rather than guessed.