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JSON Formatter

Format, validate & minify JSON

Free forever — no sign-up, nothing uploaded. Files never leave your device.

braincoder.app/use/json-formatter

JSON Formatter

Format, validate & minify JSON

Drop your file here

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Browse files

document.pdf

1.2 MB

report.pdf

860 KB

100% private

Nothing is uploaded — everything runs in your browser.

Free forever

No account or payment required.

No sign-up

Open the tool and start using it right away.

Local processing

Processing time depends on your input and device.

About this tool

Pretty-print, validate and minify JSON with instant feedback and clear error messages.

The JSON Formatter is a free, client-side utility for formatting, validating, and minifying JSON directly in your browser. Paste any raw or minified JSON and it is indented instantly as you type, so you can read API responses, configuration files, and log dumps without leaving the page.

Every keystroke is validated live: valid input shows a green badge, and invalid input shows a red badge with an error message pointing to the line and column where parsing stopped. Format with 2 or 4 space indentation, then copy either the readable version or a compact minified payload with one click.

All processing runs in your browser with zero server round-trips, so sensitive data — API keys, tokens, personal records — never leaves your machine. The tool also works offline once the app has loaded.

Key features

Everything you get with JSON Formatter — no premium upsell.

Real-time JSON formatting with 2 or 4 space indentation

Live Valid JSON / Invalid JSON badge on every keystroke

Parse errors report the line and column where parsing stopped

One-click copy of the formatted output or the minified version

Full client-side processing — JSON never leaves your browser

Works offline after the app has loaded once, with no signup required

How to use JSON Formatter

Follow the steps below to use the tool.

  1. 1

    Paste Your JSON

    Copy raw or minified JSON from your clipboard, terminal, or an API response and paste it into the input area. Formatting starts as you type.

  2. 2

    Auto-Format

    The tool indents the JSON automatically. Choose 2 or 4 spaces with the buttons above the input.

  3. 3

    Check Validity

    A green badge confirms valid JSON. Invalid input shows a red badge and an error message with the line and column where parsing stopped.

  4. 4

    Copy or Minify

    Copy the formatted output with Copy formatted, or grab the compact minified payload with Copy minified below the results.

Still free, still private — your files never leave your device.

Launch JSON Formatter

Frequently asked questions

Quick answers before you launch the tool.