JSON-LD
JavaScript Object Notation for Linked Data. The preferred format for implementing structured data that AI and search engines can parse.
What is JSON-LD?
JSON-LD is a way of writing structured data as a JSON object embedded in a page, typically inside a script tag with the type application/ld+json. The object uses a context (almost always https://schema.org) to declare its vocabulary and a type to say what kind of thing it describes, followed by properties: name, url, author, datePublished, offers and so on. Because the block is separate from the page's visible HTML, it can be added, generated or updated without touching the content markup.
Google recommends JSON-LD over the older Microdata and RDFa formats, which weave attributes into HTML elements and are harder to maintain. JSON-LD blocks can be placed in the head or body, can describe several entities on one page, and can link entities to each other with @id references, which is how a page can say that this Article was written by this Person who works for this Organization.
For AI systems the format matters less than the content, but JSON-LD's clean separation makes it easy to keep the machine-readable facts consistent with the visible ones and easy to generate from a CMS or product database. It is also the format most GEO tooling checks for when auditing a site's structured data.
Why it matters for AI search
JSON-LD is the practical way to ship structured data at scale. It lets a team define Organization, Product and Article facts once and render them on every relevant page, which is what keeps brand facts consistent across a site. Consistency is what AI engines reward when resolving entities and judging sources, so a clean JSON-LD implementation is one of the cheaper technical foundations for GEO.
Related terms
Structured Data
Standardized code (usually JSON-LD) that helps search engines and AI understand your content. Includes schemas for Organization, Product, Article, FAQ, etc.
Schema Markup
A vocabulary of tags (schemas) that help search engines and AI understand content context. Part of Schema.org standards.
Knowledge Graph
A network of entities and their relationships that AI models use to provide structured, factual answers.
LLM.txt
A proposed standard file (similar to robots.txt) that provides a Markdown-formatted map of a website for AI crawlers to consume efficiently.
Frequently asked questions
Where should JSON-LD go on the page?+
In a script tag with type application/ld+json, either in the head or the body. Google reads it in either location. Keep it in the server-rendered HTML rather than injecting it with client-side JavaScript so that AI crawlers, which do not execute scripts, can see it.
Can one page have multiple JSON-LD blocks?+
Yes. You can use several script blocks or a single block containing a @graph array of entities. Linking entities with @id makes the relationships explicit, for example connecting an Article to its author and publisher.