Free Tool

JSON Formatter & Validator

Paste JSON to format, validate, or minify it. Errors are highlighted with line numbers so you can fix issues fast.

Input

Output

How to Use

How to use the JSON Formatter

Paste your JSON

Paste raw JSON into the input area, or click 'Load sample' to try it with example data.

Choose a mode

Select Format to beautify, Minify to compress, or Tree View to explore the structure interactively.

Click Format JSON

Hit the button or press Cmd+Enter. If there's an error, you'll see the exact line and column number.

Copy the output

Click Copy to grab the formatted or minified JSON. The size comparison shows how much space you saved.

Features

Why use our JSON Formatter?

Instant Validation

Detects syntax errors immediately and shows the exact line and column number so you can fix issues fast.

Format & Minify

Beautify JSON with proper indentation or minify it to reduce file size — switch between modes with one click.

Interactive Tree View

Explore nested JSON structures by collapsing and expanding nodes. Perfect for large API responses.

100% Client-Side

Nothing is sent to any server. Your data stays in your browser — safe, private, and fast.

Size Comparison

See input vs. output file size at a glance. When minifying, see the exact percentage saved.

Keyboard Shortcuts

Press Cmd+Enter (or Ctrl+Enter) to format instantly without reaching for the mouse.

FAQ

JSON Formatter — Common Questions

Yes, completely free with no sign-up required. Use it as many times as you want — no limits.

Your JSON data never leaves your browser. All formatting, validation, and minification happens client-side using JavaScript. Nothing is uploaded or stored.

Formatting adds indentation and line breaks so the JSON is easy to read. Minifying removes all whitespace to make the file as small as possible — useful before sending data over a network.

It can't auto-fix broken JSON, but it will highlight exactly where the error is with line and column numbers so you can fix it quickly.

There's no hard limit, but very large files (over 10 MB) may slow down your browser since everything runs client-side. For most use cases it handles data instantly.

Tree view lets you collapse and expand nested objects and arrays. It's useful for exploring large JSON structures without scrolling through thousands of lines.

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