Free tool
Schema validator
A schema validator fetches one public page and reads its JSON-LD scripts. It reports whether any JSON-LD is present, whether each script is valid JSON, and whether each node has an @type, using the same notes as a Lexicon audit. It does not read microdata or RDFa, it does not promise a rich result, and it does not estimate traffic.
One public page. No account. 10 checks an hour from one network, and 3 an hour for the same site. The result is not indexed.
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