Does this JSON formatter upload my data?

No. Formatting, validation, and minification run locally in your browser with the built-in JSON parser.

Why does valid JavaScript object syntax fail as JSON?

JSON is stricter than JavaScript object literals. Keys and strings must use double quotes, comments are not allowed, and trailing commas are invalid.

Can I minify JSON with this tool?

Yes. Use the Minify button or choose the minified indentation option to remove unnecessary whitespace from valid JSON.

{ }

JSON Formatter

Pretty-print and validate JSON.

Input JSON

Formatted

{
  "hello": "world",
  "items": [
    1,
    2,
    3
  ]
}

What a JSON Formatter Does

This tool validates JSON and pretty-prints it with consistent indentation so it's easier to read. It also supports minifying — stripping whitespace so the payload is as small as possible for transmission.

How to Use It

Paste raw or minified JSON into the left panel.
The right panel updates live with formatted output.
Choose 2-space or 4-space indentation, or pick Minified to remove all whitespace.
Click Copy to put the result on your clipboard.

Common JSON Pitfalls

Trailing commas. JSON doesn't allow them. [1, 2, 3,] is invalid.
Single quotes. JSON requires double quotes around strings and keys.
Comments. Standard JSON has no comment syntax. Use JSONC or strip them first.
Unquoted keys. {name:"Alice"} is not valid JSON; keys must be quoted strings.

JSON in APIs, Configs, and Logs

JSON has become the default data exchange format on the web: REST APIs, webhooks, service configs, structured logs, and infrastructure-as-code all rely on it. A formatter is one of the most-used tools in a developer's daily workflow — right next to their terminal and text editor.

Privacy

Your JSON never leaves your browser. Everything happens locally using the built-in JavaScript JSON parser.

FAQ

Does this JSON formatter upload my data?: No. Formatting, validation, and minification run locally in your browser with the built-in JSON parser.
Why does valid JavaScript object syntax fail as JSON?: JSON is stricter than JavaScript object literals. Keys and strings must use double quotes, comments are not allowed, and trailing commas are invalid.
Can I minify JSON with this tool?: Yes. Use the Minify button or choose the minified indentation option to remove unnecessary whitespace from valid JSON.