Structured data
Also called schema markup, JSON-LD, schema.org
Machine-readable statements embedded in a page that describe what it is about, usually as JSON-LD using schema.org vocabulary. It does not change rankings directly; it changes what a result can look like and what a model can quote.
Structured data is how a page states, in a form nothing has to infer, what it is: an article with an author and a date, a product with an offer, a set of questions with answers, a trail of breadcrumbs.
It is not a ranking factor and it is not a trick. What it buys is eligibility — for a rich result, for a breadcrumb trail in place of a URL, for being quoted accurately by something that is summarising rather than linking. A page that deserves to rank does not rank better for having markup; a page that does rank presents better.
The failure mode that actually matters is disagreement. Markup claiming a price the page does not show, a rating nobody left, a date the article does not carry, or an author node that resolves to nothing. Google’s response to a site whose markup and content disagree is to stop trusting the markup, and that withdrawal is site-wide rather than per page.
Two rules make it maintainable. Generate the markup from the same data the
page renders, never transcribe it beside the page — a copy kept in step by hand
goes stale in a fortnight. And give every node a stable @id so the nodes on a
page reference one another instead of restating themselves; a reference to a
node that is not in the same graph resolves to nothing at all.
This site emits an Organization, a WebSite and a Person on every page for
exactly that reason: each page is read on its own, so declaring the publisher
once on the home page would leave every other graph pointing at an entity it
never described.
Last reviewed . Also served as markdown at /glossary/structured-data.md.