JSON Formatter

What this tool does

Paste raw JSON and it is parsed and re-printed with consistent indentation, so nested objects and arrays line up and become readable. If the text is not valid JSON, the parser error is shown instead — including where it gave up — which makes this a validator as much as a formatter.

The “Minify” option does the reverse: it strips every space and newline to produce the smallest equivalent JSON, which is what you want when embedding a payload in a config file, a query string, or a test fixture.

Common mistakes it catches

The errors that bite most often are a trailing comma after the last item, single quotes instead of double quotes around keys or strings, unquoted keys copied out of JavaScript object literals, and a stray character pasted in from a terminal or a log line. All four are rejected by the strict JSON grammar, and all four are easy to miss by eye in a long payload.

Is my data safe?

Yes. The parsing happens in your own browser using its built-in JSON engine — nothing you paste is sent to a server, so you can safely format payloads containing API responses, tokens or customer data. The page itself does load third-party ad and analytics scripts, but those never see the content of the box above.