What is Schema Markup?
Structured data added to HTML that helps search engines and AI understand what a page is about.
Written by DidYouSEO Team·Updated April 2026
Definition
Schema markup (also called structured data) is code added to a webpage in JSON-LD, Microdata, or RDFa format that explicitly describes the content on the page using a standardized vocabulary from Schema.org. Common schema types include Organization, Product, Article, FAQ, BreadcrumbList, and SoftwareApplication. Search engines and AI crawlers use this data to understand page content without ambiguity.
Why it matters for SEO
Schema markup enables Google to show rich results in search - star ratings, FAQ dropdowns, product prices, event dates. These rich results get higher click-through rates than standard blue links. For AI search visibility, schema markup is particularly important: AI crawlers use it to understand your brand, product, and content precisely, making it more likely they reference you in responses.
How to check schema markup
DidYouSEO's schema validator checks whether your pages have valid structured data, identifies which schema types are present, and flags validation errors. Run it on any URL to see your schema health.
Check it on your site - free
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