Free Online Tool

JSON Formatter & Validator

Free JSON formatter and validator. Paste messy JSON and instantly format, validate, and beautify it with syntax highlighting and error line numbers.


















What is this tool?


JSON (JavaScript Object Notation) is the most widely used data format for APIs, configuration files, and data storage. A JSON formatter takes messy, minified, or invalid JSON and transforms it into a clean, indented, human-readable format.


Why use this tool?


Manually formatting JSON is tedious and error-prone. Our browser-based formatter validates your JSON syntax, highlights errors with exact locations, and lets you switch between formatted and minified views instantly.


Tips & Best Practices


    

  • Paste API responses directly to debug
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  • Use Minify to reduce payload size
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  • Check for trailing commas — JSON doesn't allow them
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  • Validate before sending to APIs
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Frequently Asked Questions


Is my data safe?


Yes. Everything runs in your browser. No data is ever sent to a server.


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