Free JSON Validator

Validate JSON with detailed error messages showing exact line and position. Auto-fix trailing commas, single quotes, and other common mistakes. Pretty print, view stats, and optionally validate against a JSON Schema.

Drop a JSON file here or click to upload
Paste or upload JSON to validate
Error

Formatted Output


      
    

Schema Validation (Optional)

Paste a JSON Schema to validate your data against it. Supports basic JSON Schema draft-07 properties: type, required, properties, items, enum, minimum, maximum, minLength, maxLength, pattern.

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Open source

QTool.io on GitHub

269 free tools. No signup. Open source. Built by Christian Bucher.

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