Glossary

What is JSON-LD?

Also known as JavaScript Object Notation for Linked Data, JSON-LD structured data

Definition

JSON-LD is a way of writing structured data as a small block of code inside a web page. It describes the page's content using schema.org terms, and it is the format Google recommends for structured data.

Key points

JSON-LD adds structured data as one self-contained script block on a page.
Google recommends it because it is the easiest format to add and maintain.
Blocks that use stable IDs and point to each other build a connected picture of your business.

What does it mean in practice?

A physiotherapy clinic wants search engines to know its name, address, phone number and opening hours. With JSON-LD, it adds one script block to the page's HTML. Inside, it states that the page is about a LocalBusiness, then lists each fact as a labelled value. Visitors never see it, but crawlers read it.

Because it sits in its own block, JSON-LD is easier to add and maintain than older formats that wrap tags around visible text. Google says it recommends JSON-LD where your setup allows it. The format itself is a W3C standard.

Why does it matter for AI search?

JSON-LD is the usual way to publish schema markup, so it is how most sites tell machines who they are. Blocks that use stable @id values and point to each other build a small connected graph of your business. An Article can point to its author and its publisher, for example.

A few habits help. Keep the facts identical to what is on the page. Avoid adding types you cannot back up. Test changes with Google's Rich Results Test.

The schema generator in Axiom GEO builds copy-paste JSON-LD with no AI and no credits. Our guide to schema markup for AI search covers what to include.

These terms connect to JSON-LD.

Schema markup, the vocabulary JSON-LD is written in.
Knowledge graph, what linked JSON-LD blocks build.
Entity, the thing each block describes.

Common questions

Is JSON-LD the same as schema markup?

Not quite. Schema markup is the vocabulary of types and properties from schema.org. JSON-LD is one format for writing that vocabulary into a page. Microdata and RDFa are the other two formats Google supports, but JSON-LD is the one it recommends.

Where should JSON-LD go on a page?

It goes in a script tag with the type application/ld+json, usually in the head of the page, though Google also reads it in the body. The facts inside it should match what visitors can see on the page.

Reviewed 26 September 2026

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