JSON Formatter & Validator

Paste your JSON to format, validate, or minify it instantly. Everything runs in your browser — nothing is sent to a server. Syntax errors are caught in real time with line-level feedback.

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Output

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Frequently Asked Questions

What does a JSON formatter do?: A JSON formatter takes raw or minified JSON data and restructures it with proper indentation and line breaks, making it easy to read and debug. It can also validate your JSON to ensure it follows the correct syntax.
How do I validate JSON online?: Paste your JSON into the input field and click Format. If the JSON contains syntax errors, the tool will display an error message with the approximate line number where the issue was found. Valid JSON will be formatted and shown in the output panel.
What is the difference between formatting and minifying JSON?: Formatting adds indentation and line breaks to make JSON human-readable. Minifying does the opposite — it removes all unnecessary whitespace to produce the smallest possible output, which is ideal for APIs and data transfer.
Is my JSON data safe when using this tool?: Yes. All processing happens entirely in your browser. Your JSON data is never sent to any server, stored, or logged. The tool runs 100% client-side using JavaScript.

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