JSON Formatter

Format, validate, and minify JSON instantly. Beautify JSON for readability, catch syntax errors, and copy clean output in one click.

JSON Formatter
Format, validate, and pretty-print JSON instantly - runs locally in your browser.
Options
Input JSON
Paste JSON exactly as-is. Errors will show on the right.
OUTPUT (VALID)
{
  "hello": "world",
  "n": 123,
  "ok": true
}
Formatted JSON ready to copy.
Tip: Paste JSON on the left. If it’s valid, you’ll get formatted output on the right. Use indentation to match your style guide.
Runs locally in your browser. Nothing is uploaded or stored.

How the JSON Formatter works

JSON (JavaScript Object Notation) is a common data format used in APIs, configuration files, and web applications. A JSON formatter makes the data easier to read by applying indentation and line breaks.

This tool does two main jobs: (1) validates your JSON (checks if it’s valid syntax) and (2) formats or minifies it depending on what you need. If the JSON is invalid, the tool shows an error so you can fix issues quickly.

Because everything runs locally in your browser, your data stays on your device - nothing is uploaded or stored.

  1. Validate: Detects invalid JSON and shows a clear error message.
  2. Format / Beautify: Pretty-prints JSON with indentation for readability.
  3. Minify: Removes whitespace to reduce size for storage or sharing.
  4. Copy output: Copy the formatted result in one click.

When to use a JSON formatter

If you work with APIs, logs, or config files, you’ll regularly run into JSON that’s hard to read. Formatting turns one-line JSON into a structured view so you can quickly spot missing fields, nesting issues, or unexpected values.

Minifying is useful when you want compact JSON for embedding, sending, or storing. Formatting is better for debugging, reviewing, and documentation.

  1. API debugging: Inspect API responses and payloads quickly.
  2. Config files: Clean up JSON configs before committing.
  3. Logs: Make JSON logs readable when troubleshooting.
  4. Code reviews: Share clean, consistent JSON snippets.

Tips for clean JSON

If you get an error, check for common problems like trailing commas, missing quotes around keys, or mismatched braces/brackets.

For consistent style, stick to one indentation level (commonly 2 spaces) across your project. It reduces diffs and makes reviews easier.

  1. No trailing commas: JSON does not allow trailing commas like some JS objects do.
  2. Quotes matter: Keys and string values must use double quotes in strict JSON.
  3. Match brackets: Every { needs a } and every [ needs a ].

FAQ

Is this JSON formatter free to use?

Yes. This JSON formatter is completely free and requires no sign-up.

Does this tool upload or store my JSON?

No. All formatting and validation happens locally in your browser. Your JSON never leaves your device.

Can I validate JSON with this tool?

Yes. The formatter checks your JSON syntax and shows an error message if the JSON is invalid.

What’s the difference between formatting and minifying JSON?

Formatting (beautifying) adds whitespace and indentation to make JSON easier to read. Minifying removes whitespace to make the JSON smaller for storage or transmission.

Does it support large JSON files?

Yes. It can handle large JSON inputs, but extremely large files may be limited by your browser’s memory/performance.

What browsers are supported?

The JSON Formatter works in all modern browsers, including Chrome, Firefox, Edge, and Safari.

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