GetPicked

AI search glossary

Review schema and AggregateRating: rules for star ratings in search

Review schema is structured data using the schema.org Review and AggregateRating types to describe a single review of an item, or the average rating from many reviews, so search engines can show star ratings and review counts.

Also called: review snippet markup, aggregate rating schema, AggregateRating schema, star rating schema

Why it matters for AI search

AI assistants asked for the best option in a category lean on evidence that other people rate it well. Ratings marked up on product pages, and reviews of you on independent sites, give engines numbers and quotes they can cite. Because Google ignores self-serving business ratings, the reviews that carry most weight for a company are the ones it does not control, on marketplaces and review platforms.

How review schema works

There are two main types. Review describes one review: who wrote it (author), what it is about (itemReviewed) and the score (reviewRating with a ratingValue). AggregateRating summarizes many: schema.org defines it as the average rating based on multiple ratings or reviews, with ratingValue, ratingCount and reviewCount.

The usual pattern is to nest the rating inside the thing being rated:

{
  "@context": "https://schema.org",
  "@type": "Product",
  "name": "Ridgeline 4 trail shoe",
  "aggregateRating": {
    "@type": "AggregateRating",
    "ratingValue": "4.4",
    "reviewCount": "89"
  }
}

Google lists supported item types including Product, Book, Course, Event, Recipe, SoftwareApplication, LocalBusiness and Organization. The default scale is 1 to 5; set bestRating and worstRating if you use another.

Google's self-serving review rule

This is the rule that catches most businesses. If the entity being reviewed controls the reviews about itself, its pages using LocalBusiness or Organization markup are not eligible for review stars. Google gives the example of a business showing reviews through an embedded third-party widget: still self-serving. Other rules from the same documentation:

  • Reviews must be readily visible on the marked-up page.
  • Reviews must be about a specific item, not a category or a list.
  • Do not aggregate reviews or ratings from other websites.
  • Fake reviews and undisclosed incentivized reviews are not allowed.

In practice: a store can mark up customer ratings on its product pages, but it cannot put stars on its home page by rating itself.

Google says no special structured data is needed for AI Overviews or AI Mode, so markup alone will not get you cited. What helps is the evidence behind it. An engine comparing products can quote a 4.4 rating from 89 reviews if it is on the page in plain text. For a company as a whole, engines look at what others say: review platforms, marketplaces, forums and press. Those are the brand mentions you cannot mark up yourself, and they are often what an AI answer cites.

How to check and fix it

  1. Remove AggregateRating from Organization or LocalBusiness markup that rates your own business.
  2. Keep product ratings, and make sure the number and count shown on the page match the markup.
  3. Delete any markup that copies ratings from another site.
  4. Test product templates in Google's Rich Results Test.

Ratings are most often attached to Product schema. For business location markup and why it cannot carry self-reviews, see LocalBusiness schema. The wider picture is in schema markup.

Questions

What is a self-serving review in Google's terms?
A review the reviewed entity controls about itself. Google says pages using LocalBusiness or Organization markup are not eligible for star review snippets when the business controls those reviews, and that includes reviews shown through an embedded third-party widget.
Can I mark up ratings from Google, Yelp or Trustpilot on my site?
No. Google's guidelines say not to aggregate reviews or ratings from other websites. Only mark up reviews collected on your own site, and only when they are visible on the page.
What does AggregateRating require?
Google requires ratingValue, at least one of ratingCount or reviewCount, and the item being rated (unless the rating is nested inside that item, such as a Product). If bestRating is omitted, Google assumes a 5-point scale.
Can product pages still show stars?
Yes. Product is one of the supported item types, and the self-serving restriction applies to LocalBusiness and Organization. The reviews must be real, visible on the page and about that specific product.

Related terms

Sources