Check JSON-LD structured data
A local first pass that catches the two mistakes that matter: broken JSON, and a required property that is simply not there.
How Schema Validator works
The analysis runs against the markup you paste, using the same rules a crawler applies. Nothing is fetched from your site, which is also why it cannot see what a live crawl would. Unpublished pages and drafts can be checked here without being exposed to anyone.
That is the whole architecture: static files, one script, no upload endpoint to leak or log. Close the tab and the work is gone.
Good to know
- Works offline once loaded, including on flights and in locked-down networks.
- No file size limit beyond your device's own memory.
- Free to use, with no account and no usage counter.
- Results are produced locally, so they are not logged or shared with anyone.
Questions
Is this Google's validator?
No, and it says so. It checks JSON syntax, @context, @type and the required properties for the common types. Google's Rich Results Test is the final authority because it applies Google's own rules.
Does it handle @graph?
Yes — every node inside a @graph is validated separately, which is how most real-world schema is written.
Which types does it know?
Article, NewsArticle, BlogPosting, FAQPage, Question, Product, Offer, Organization, LocalBusiness, Person, BreadcrumbList, WebSite, WebApplication and VideoObject.
Does it fetch my page?
No. It cannot — the browser blocks cross-origin reads — and it would mean sending your URL to a proxy. Paste the JSON instead.
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