• 100% Free
  • No Sign-Up
  • No Credit Card
  • No Free Trial
  • No Pro Tier
  • No Watermarks

Nothing is uploaded. Just open it and start.

A JSON formatter that stays out of your way

Paste JSON, watch it format or minify live, and catch syntax errors before they cost you a debugging session. No sign-up, no watermarks, nothing between you and your data.

Live validation

Errors are flagged as you type, with the exact line and column pinpointed — no more hunting through a wall of text.

Format & minify, live

Switch between beautified and compact output any time. Both panes stay in sync with your input as you edit.

Upload & download .json files

Load a file straight from disk, or save your formatted or minified result back to one.

100% private, 100% client-side

Your JSON never leaves your browser. There's no server round trip, ever.

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Frequently asked questions

What's the difference between Format and Minify?
Format pretty-prints your JSON with 2-space indentation so it's easy to read. Minify strips all whitespace to produce the smallest possible payload. Both stay live-synced to whatever you've pasted or typed.
Is my JSON data sent to a server?
No. Every parse, format, and minify happens entirely in your browser using the built-in JSON parser — nothing is uploaded, logged, or stored anywhere.
What size of JSON file can I upload?
Up to 10MB per file via the Upload button. Pasting directly into the editor has no hard limit.
Does it fix invalid JSON automatically?
No — it validates your JSON and points you to the exact line and column of the problem so you can fix it yourself, rather than silently guessing at a "repair."
Is the JSON Formatter really free?
Yes. There's no account to create, no card to enter, and no trial clock ticking in the background. Formatting, minifying, validation, and file upload and download are all included, with no document size limit. Hosting is paid for by a single unobtrusive ad slot and nothing else.
Is there anything to install or register for?
No. It's a plain web page: no account, no extension, no desktop app, no email capture. Paste JSON and it formats and validates as you type.