JSON Formatter & Validator

About

How to use

1. Paste your JSON into the box.
2. Choose the indent size and click 'Format'; use 'Minify' for a single line.
3. Copy the result. Invalid JSON shows an error message.

Common JSON mistakes

If you get an error when you click “Format”, it is usually one of these:

Trailing comma

{"a": 1,} is invalid. There must be no comma after the last item.

Single quotes

JSON only accepts double quotes: not {'a':1} but {"a":1}.

Unquoted key

{a: 1} is invalid; keys must be in double quotes: {"a": 1}.

Beautify vs Minify

Beautify adds readable indentation; Minify strips all whitespace into one line.

Frequently Asked Questions

Is my JSON sent to a server?

No. Parsing and formatting happen entirely in your browser, so sensitive data never leaves your device.

How do I find invalid JSON?

When you click 'Format', invalid JSON triggers an error message that usually explains where the problem is.

What does minify do?

It removes all unnecessary whitespace and line breaks to collapse the JSON into one line, reducing its transfer size.