Structured Data

Structured data is code in a standardized format, added to a page to describe its content in a language machines read unambiguously. Where a person immediately sees that a page covers a product at 49 euros with a 4.6-star rating, a search engine needs the same facts served as data. Structured data is exactly that translation.

How it works

Most implementations use the schema.org vocabulary, usually as JSON-LD, a small script in the page's HTML. Content is marked up as types and properties: an article with an author and a publication date, a product with price and stock status, an FAQ with questions and answers.

Google uses the markup in two ways. It helps the algorithm understand the page's content and the entities on it, and it makes the results eligible for rich results: stars, prices and other expanded displays that usually pull more clicks than a plain blue link.

Structured data is also one of the parts of SEO that gained new weight with AI search. The more precisely content is described, the easier it is for classic search engines and for models like ChatGPT and Perplexity to cite it with the right name, price and facts.

One rule sits above the rest: the markup has to reflect what is visibly on the page. Anything else conflicts with Google's guidelines and can cost rich results rather than earn them. The guide to structured data covers how the markup is implemented in practice.