JSON Formatter

Paste JSON, get it pretty-printed or minified instantly, with line numbers and an exact error location if something's broken.

Tool 01 — parse → format Idle

Input0 chars

Output0 chars

Pretty-print Minify

Indent

Runs entirely in your browser. Formatting happens client-side with no network request — safe for configuration, fixtures or anything you'd rather not paste into a server-side tool.

Examples

{"a":1,"b":[2,3]}→{ "a": 1, "b": [2, 3] }

{"id":"x","nested":{"ok":true}}→2-space indented, multi-line

{"trailing":1,}→Error: trailing comma at line 1, col 15

FAQ

How do I format JSON?

Paste JSON into the input panel on the left. It's pretty-printed automatically with your chosen indent width, or minified if you switch modes.

What is JSON pretty-printing?

Pretty-printing adds consistent indentation and line breaks so nested objects and arrays are easy to scan, without changing the underlying data.

Does this validate JSON too?

Yes — invalid JSON shows an error with the exact line and column. For schema-level checks, see the JSON Validator.

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