JSON Formatter & Validator

Beautify, minify, and validate JSON instantly.

Free online JSON formatter & validator

This JSON formatter beautifies, minifies, and validates JSON right in your browser. Paste an API response, a config file, or any JSON snippet and it is checked instantly — valid data is confirmed as you type, while a syntax mistake surfaces the parser's own error message so you can fix it fast. Then pretty-print the JSON with your preferred indentation, or compress it down to a single line for production. Nothing you paste ever leaves your device.

How to format JSON

  1. Paste or type your JSON into the input box on the left.
  2. Watch the status line confirm Valid JSON or describe any parse error live.
  3. Pick your indentation — 2 spaces, 4 spaces, or a tab — from the selector.
  4. Click Beautify to pretty-print, or Minify to strip whitespace.
  5. Use Copy to grab the formatted result, or Clear to start over.

Beautify vs. minify

Beautified JSON is indented and spread across multiple lines, which makes it easy to scan while debugging or reviewing an API payload. Minified JSON removes every unnecessary space and newline to shrink the file, which matters when you ship data over the wire or paste it into code. Both keep your values identical — only the whitespace changes. If you also need to encode a payload for transport, try the Base64 encoder, or clean up copied text with the remove line breaks tool.

Private and dependency-free

Every operation uses your browser's native JSON parser, so there are no network requests and no third-party libraries. That makes this a safe, fast way to validate confidential data such as tokens, user records, or internal API responses without ever exposing them.

Frequently asked questions

What does a JSON formatter do?

A JSON formatter takes raw, minified, or messy JSON and re-prints it with consistent indentation and line breaks so it is easy to read. This tool also validates the JSON as you type, so if a comma, bracket, or quote is out of place you see the exact parser error straight away.

What is the difference between beautify and minify?

Beautify (or "pretty-print") adds indentation and newlines to make JSON human-readable, which is ideal for debugging and documentation. Minify strips every optional space and line break to produce the smallest valid JSON, which is best for sending data over the network or embedding in code.

Is my JSON uploaded to a server?

No. All parsing, formatting, and validation happen entirely in your browser using the built-in JSON engine. Your data is never sent, stored, or logged, so it is safe to format private API responses, config files, and confidential payloads.

Why am I getting a JSON parse error?

The most common causes are trailing commas, single quotes instead of double quotes, unquoted keys, missing closing brackets, or comments — none of which are valid in strict JSON. The error message shows the parser's own description (often with a position) so you can jump to the problem.

Can I choose the indentation size?

Yes. Use the indent selector to beautify with 2 spaces, 4 spaces, or tab characters. Two spaces is the most common convention for JSON and JavaScript projects, while tabs suit teams that prefer tab-based indentation.

Does formatting change my data?

No. Beautifying or minifying only changes whitespace, never the values, keys, or structure. The output is parsed from and re-serialized to the exact same data, so numbers, strings, booleans, and nesting are preserved.