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JSON Schema Validator

Check a JSON document against a schema before using it in an API or configuration workflow. Choose draft 2020-12 or draft-07 and get a validation report with the first failing instance path, schema path and rule.

🔒 100% private — files never leave your browser

Result

How to use the JSON Schema Validator

  1. 1 Paste or import your JSON document and its JSON Schema in the two editors.
  2. 2 Select the matching schema draft and validate. Read the first failing path and rule in the report.
  3. 3 Correct the document or schema and run again, then copy or download the validation report.

Frequently asked questions

Are external schema references downloaded?

No. References must resolve within the pasted schema or its selected draft meta-schema. Remote references and asynchronous validation are unsupported; nothing is fetched from a $ref address.

What does the validator check?

Ajv validates in strict mode with standard format checks, including email and date-time. It reports the first failure without coercing types, adding defaults or deleting properties. Strict-mode schema errors must be fixed before document validation.

Why are there size and time limits?

Schemas can contain expensive regular expressions or recursion. Each input is limited to 500 KB and validation runs in a terminable Worker with a 10-second timeout. Only draft 2020-12 and draft-07 are offered.

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