AggregateRating Schema

What AggregateRating is

AggregateRating is a schema.org type that summarizes many individual reviews into one score: an average rating and a count. It is a property you nest inside a parent item, most commonly a Product, but also Recipe, Book, Course, LocalBusiness, SoftwareApplication, and a handful of others. Google reads it and, when everything checks out, renders the familiar star line under your title in the SERP.

The core fields are simple. ratingValue is the average score. bestRating and worstRating define the scale (default 5 and 1 if you omit them). And you need a count: either ratingCount, reviewCount, or both. Miss the count and Google has no evidence the rating represents real volume, so it will not draw stars.

Why the stars are worth the effort

A star line is one of the few things that makes an organic result visibly different from the nine others on the page. It occupies vertical space, it signals social proof before the click, and in competitive categories it is often the difference between a result people skim past and one they trust. Google does not publish a fixed uplift number and results vary by query and vertical, so treat any single "stars add X percent CTR" claim you read online with skepticism. The mechanism is real; the exact number is situational.

The flip side matters more than the upside. Review snippets are governed by Google's structured data policies, and the penalty for gaming them is severe. Mark up ratings that are not visible on the page, self serve ratings for your own business, or numbers that do not match what users see, and you risk a manual action that strips rich results across the whole site. This is one of the areas where cutting corners genuinely bites.

Valid markup vs the common ways it breaks

A minimal valid example

Here is AggregateRating nested in a Product, using JSON-LD, which is the format Google recommends:

{
  "@context": "https://schema.org",
  "@type": "Product",
  "name": "Acme Trail Runner",
  "aggregateRating": {
    "@type": "AggregateRating",
    "ratingValue": "4.4",
    "reviewCount": "218",
    "bestRating": "5",
    "worstRating": "1"
  }
}

Note the count is present, the scale is explicit, and every one of those 218 reviews should be visible somewhere on that product page. The markup describes the page, it does not invent content that is not there.

Field reference

How to detect and validate

1. Rich Results Test. Google's own tool at the URL or code level tells you whether the AggregateRating is valid, what item type it attached to, and which fields are missing. This is your first stop.
2. Schema Markup Validator. The schema.org validator catches structural mistakes the Rich Results Test may not flag, like a misspelled property or a broken nesting.
3. Search Console, Enhancements. The Review snippets report shows valid, warning, and error items across your indexed pages at scale, plus any manual actions under the Security and Manual Actions section.
4. Screaming Frog. Enable structured data extraction and crawl the site to find every page missing AggregateRating or emitting errors, which beats checking pages one at a time.
5. View source. Confirm the JSON-LD actually renders in the HTML and is not injected only after a JavaScript event Google might not wait for.

What good looks like

The parent item is a type Google supports for review snippets. AggregateRating carries a real average and a real count that match the reviews shown on the page. The Rich Results Test returns valid with no warnings, the Search Console Review snippets report is clean, and the stars appear in the live SERP. Nothing is fabricated, nothing is hidden, and the markup would survive a spot check by a human reviewer.

FAQ