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Tools/JSON Formatter

JSON Formatter & Validator

Paste messy or minified JSON to instantly format, validate, and beautify it — with clear error messages if something's wrong. Runs entirely in your browser.

Frequently Asked Questions

Is my JSON data uploaded anywhere?

No — parsing and formatting happen entirely in your browser using JSON.parse/JSON.stringify. Nothing you paste is sent to a server.

What does the error message tell me?

It's the exact parsing error from your browser's JSON parser, usually pointing to the type of problem (unexpected token, trailing comma, unquoted key) so you can find and fix it quickly.

Can I minify JSON instead of formatting it?

Yes — click "Minify input" to collapse your JSON to a single compact line, useful for reducing payload size before sending it somewhere.

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