JSON Formatter & Validator

What is JSON Formatting?

JSON (JavaScript Object Notation) is a text-based data format used by virtually every web API and application. When JSON is transmitted or stored, it is often compacted into a single line with no whitespace to save bytes. While efficient for machines, this raw form is nearly impossible for humans to read.

JSON formatting — also called pretty-printing or beautifying — parses the JSON and re-serializes it with consistent indentation and line breaks. The result is structured, readable output where you can immediately see the nesting of objects and arrays.

Features

• Format / Pretty-print — Adds indentation (2 or 4 spaces) and line breaks for readability.
• Minify / Compress — Removes all unnecessary whitespace to reduce size.
• Validate — Instantly shows whether your JSON is syntactically valid, with the exact error message if not.
• Copy to clipboard — One click to copy the formatted output.
• 100% client-side — Your data never leaves your browser.

How to Use This JSON Formatter

1. Paste or type your JSON into the Input box.
2. Choose an indent size (2 or 4 spaces).
3. Click Format JSON to pretty-print, or Minify to compress.
4. Check the status bar — a green indicator means your JSON is valid; red shows the parse error.
5. Click Copy to copy the output to your clipboard.

Frequently Asked Questions

What is JSON?

JSON (JavaScript Object Notation) is a lightweight, text-based data interchange format. It is easy for humans to read and write, and easy for machines to parse and generate. JSON is widely used for APIs, configuration files, and data storage.

What does "formatting" or "pretty-printing" JSON do?

Formatting adds indentation and line breaks to make JSON easier to read. Raw or minified JSON can be a single long line with no whitespace. A formatter parses the JSON and re-serializes it with consistent indentation (2 or 4 spaces), making the structure immediately clear.

What is the difference between formatting and minifying JSON?

Formatting adds whitespace to improve readability. Minifying removes all unnecessary whitespace to reduce file size — useful before sending JSON over a network or embedding it in code.

How do I validate JSON?

Paste your JSON into the input box above. The tool will attempt to parse it using the browser's built-in JSON.parse(). If the JSON is valid, a green "Valid JSON" indicator appears. If there is a syntax error, the exact error message is shown so you can fix it.

Is my data safe? Is it sent to a server?

Yes, completely safe. This tool runs entirely in your browser using JavaScript. No data is ever sent to any server. Your JSON never leaves your device.