Schema Markup Validator and Checker by FullSchema

Schema markup validator and structured data checker. Test any page's JSON-LD against Google's rich result rules in one click.

Schema Markup Validator and Checker tests the structured data on the page you have open. Click the icon and a side panel lists every error and warning in the page's JSON-LD and Microdata, checked against Google's rich result rules and the schema.org vocabulary. It reads the page your browser already loaded, not a copy fetched by a server. That means you can test localhost and staging sites, pages behind a login, and pages that block bots. Schema added by JavaScript or Google Tag Manager is checked too. Use it as a schema markup checker while you build a site, or as a quick website schema checker when you look at someone else's. For each page you get: - A short verdict, like "2 errors to fix" or "No errors or warnings" - The Google rich results the markup is eligible for (product snippets, merchant listings, breadcrumbs, site name and more), and what's missing where it isn't - Every error in plain English with what to change, then the warnings - The schema.org types on the page, such as Product, LocalBusiness, Article or FAQPage - Fields Google recommends that aren't in the markup yet - The code, block by block, with a copy button The schema validation rules are the same ones behind the free FullSchema Schema Markup Validator on our website, and they follow Google's structured data documentation. They run on our server, so they stay current without an extension update. If you also want Google's own answer, the panel links to the Rich Results Test, with the address filled in for public pages. There's no account and no sign-in. The extension doesn't change the pages you visit and only reads a page when you click its icon. If the markup is missing or broken, the panel links to FullSchema, a schema markup generator that reads the page and writes JSON-LD from what it shows. Privacy: when you click the icon, the page's address and HTML are sent to fullschema.app for the check. They aren't stored or shared. Full policy: https://fullschema.app/privacy