Review Schema

Review schema is schema.org markup that attaches a rating to the thing it rates: a single Review with an author and a reviewRating, or an AggregateRating with a ratingValue and a count. It states, in a form a machine can parse, that customers have rated the business and how.

What the markup has to contain

Google’s requirements for a review snippet are short. A Review needs an author, a Person or an Organization named in under 100 characters; an itemReviewed of a specific type; and a reviewRating with a ratingValue. An AggregateRating needs the itemReviewed, a ratingValue, and either a ratingCount or a reviewCount. The item has to be one of the types Google supports for the feature, which include LocalBusiness, Product, Organization, Book, Course, Event and Recipe.

The self-serving rule

Google will not show stars for a LocalBusiness or Organization page whose reviews are controlled by the entity being reviewed, which covers reviews on the business’s own site and reviews pulled in through an embedded widget. Ratings have to come from users rather than from an editor compiling them, and fake or undisclosed incentivised reviews are forbidden in markup and on the page. So the markup on a business’s own site does not earn it a star in Google. It still tells any machine that reads the page that a rating exists, how high it is and how many people gave it. Whether an assistant weighs that is not documented by any assistant, and this site has not measured it.

What the audit found

Of 9,483 small-business sites this site audited, 64.7% showed no review signal a crawler could read: no rating markup and no review quoted in the page text. 8.9% carried rating schema. Most of these businesses have reviews on Google; their sites do not say so in any form a fetcher receives. The write-up has the rest.

A common question

Is review markup on a business's own site worth adding if the stars never show?

The stars will not appear, because Google withholds them for a LocalBusiness or Organization page whose reviews the reviewed entity controls, which covers ratings hosted on the site and ratings pulled in through an embedded widget. The markup still tells any machine that reads the page that a rating exists, how high it is and how many people gave it. Whether an assistant weighs that is not documented by any assistant, and this site has not measured it. In the audit, 64.7% of 9,483 sites showed no review signal a crawler could read.

Sources

Requirements and the self-serving rule: Google Search Central, review snippet. Type: schema.org/AggregateRating. The audit figures are this site’s own; sample drawn per metro and trade, percentages describe the sample.