JSON-LD.
Learn what JSON-LD means in modern search and SEO.
The preferred format for adding structured data markup to web pages — embedded as a script tag rather than mixed into HTML attributes.
JSON-LD (JavaScript Object Notation for Linked Data) is a method of encoding structured data as a `<script type='application/ld+json'>` block in the HTML `<head>` or `<body>`. It is Google's preferred structured data format because it keeps semantic markup completely separate from HTML presentation, making it easier to add, update, and validate without touching the visible page layout.
JSON-LD vs Microdata vs RDFa
JSON-LD, Microdata, and RDFa are all accepted by Google for structured data. Microdata and RDFa embed attributes directly into HTML elements, which requires developers to modify the page template for every schema property. JSON-LD sits in a separate script block that can be updated independently—reducing the risk of breaking visible HTML when schema changes are needed.
Implementing JSON-LD for SEO
A JSON-LD block specifies the @context (schema.org), @type (Article, Product, FAQPage, BreadcrumbList, etc.), and all required properties for that schema type. Google's Rich Results Test validates JSON-LD for errors and previews the rich result it may generate. Schema.org documents all supported types and their required vs recommended properties.
Related Terms
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