Overview

application/ld+json is the media type for JSON-LD (JSON for Linked Data), which adds a semantic context (@context) to ordinary JSON so data carries machine-understandable meaning. On the web it is most widely used as structured data (schema.org) for search engines.

Details

JSON-LD is a W3C standard where `@context` maps each key to a global identifier (an IRI), letting distinct datasets link together (Linked Data). With the `+json` structured suffix its foundation is JSON, so ordinary JSON parsers read it and clients that Accept application/json remain compatible.

In SEO practice you embed it inside HTML as `<script type="application/ld+json">...</script>` to declare schema.org types like Article, Product, Breadcrumb, or FAQPage. Google parses this block to render rich results (star ratings, breadcrumbs, FAQ accordions). That inline script is treated as data, not executed; you use Content-Type: application/ld+json only when the HTTP response itself is JSON-LD.

Syntax

e.g. Content-Type: application/ld+json

File extensions

Notes

• Inline JSON-LD in HTML is invisible on screen, so if it disagrees with the visible content it can be flagged as spam — reflect the actual page.
• It is fundamentally JSON, so the same UTF-8, quoting, and no-trailing-comma rules apply; a syntax error makes the whole rich result be ignored.
• In content negotiation, application/ld+json is a specialization of application/json, so make Accept priorities explicit.

Related types

Related headers