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JSON Schema validator
Compare a JSON document with a schema directly in your browser. Each error includes its path, the failed rule and a clear explanation.
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- Instant
- Free
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- Works offline
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Why use this tool?
Validate a JSON document against a schema without uploading your data. The tool checks common rules including types, required properties, numeric limits, string lengths, arrays, allowed values and schema combinations.
Smart processing
Generate, convert, or validate technical data with purpose-built controls.
Supported formats
Technical formats and syntaxes suited to each generator, converter, or validator.
Save time
Get a clean, ready-to-use result in seconds without installing software or configuring a complex workflow.
Guide
How to use this tool
- 1
Paste the JSON document
Enter the data you want to inspect in the first editor.
- 2
Add the schema
Describe the expected structure with JSON Schema rules in the second editor.
- 3
Review each error
Run the validation and use the reported path and rule to fix every issue.
Tips and best practices
- Start with type, required and properties before adding more precise constraints.
- Use additionalProperties: false when unexpected fields must be rejected.
- This tool covers the most common rules but does not claim full conformance with every official JSON Schema draft.
Frequently asked questions
Are my documents uploaded?
No. The document and schema are processed locally in your browser.
Which rules are supported?
The tool supports type, required, properties, items, enum, const, common string, number and array limits, additionalProperties, allOf, anyOf, oneOf and not.
Can I validate a very large file?
Reasonably large files work, but the practical limit depends on browser memory and schema complexity.
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