A collaborative vocabulary for structured data markup on web pages, supported by Google, Microsoft, and Yahoo.
Schema.org is a collaborative, community-driven project founded by Google, Microsoft, Yahoo, and Yandex to create a shared vocabulary for structured data markup on web pages. It provides a collection of schemas — types, properties, and their relationships — that webmasters can use to mark up their HTML content in ways that are understood by major search engines and AI systems. Schema.org covers thousands of entity types from Person and Organization to Recipe, Event, Product, and MedicalCondition.
Schema.org has become the de facto standard for communicating structured data to AI systems. As LLM-powered search engines and AI assistants crawl the web, Schema.org markup enables them to accurately extract structured facts from web pages. Websites with comprehensive Schema.org markup are more likely to be cited by AI systems, appear in rich search results, and be included in knowledge graph extractions.
Schema.org markup is embedded in web pages using JSON-LD (recommended), Microdata, or RDFa. Each page describes the primary entity it represents using a Schema.org type and its properties. For example, a product page uses schema:Product with properties like name, price, availability, and aggregateRating. Search engines and AI crawlers parse this markup to build structured representations of web content without relying solely on natural language understanding.
A local restaurant adds Schema.org markup to their website: Restaurant type with properties for name, address, telephone, openingHours, servesCuisine, and menu. Google uses this to populate the restaurant's Knowledge Panel in search results, showing hours, location, and cuisine type — and to answer voice queries like 'Is [restaurant name] open right now?' with accurate, structured data.