100% Free & Client-Side

JSON Formatter & Validator

Format, validate, and minify JSON — right in your browser. No upload, no signup, no limits.

Compare vs Postman

How It Works

  • Paste your raw JSON or upload a .json file
  • Click "Format" to pretty-print with your preferred indent
  • Click "Validate" to check syntax and see line/column errors
  • Click "Minify" to collapse to a single line
  • Copy output to clipboard with one click
  • Toggle dark/light theme for comfortable viewing
  • Your data never leaves your device

Why Not Postman?

  • Free forever — no $15/mo subscription
  • No uploads — formatting happens locally in your browser
  • No signup — just open and use
  • Privacy-first — your JSON data never sent to a server
  • Lightweight — runs in any modern browser
  • Works offline — after first load

Frequently Asked Questions

Is this really free? Yes. No signup, no trial, no hidden fees. It runs entirely in your browser.
Can I validate JSON? Yes — click "Validate" and it will show errors with line and column numbers if the JSON is invalid.
What JSON sizes does it handle? As large as your browser can handle — there's no server-side limit.
Is my data private? Yes. Everything runs client-side in your browser. Your JSON is never uploaded anywhere.

JSON Formatter

vs Postman