JSON Formatter & Validator

What a JSON formatter is for

JSON is easy for machines to read but painful for people once it arrives as one long, unbroken line. A formatter takes that dense string and re-indents it into a clear tree, so you can actually see which keys belong to which object, where an array starts and ends, and how deep the nesting goes. It's the fastest way to make an API response, a config file, or a copied log entry readable again.

When you'd reach for it

Common moments: you've pinged a REST endpoint in your terminal and got back a wall of text; you're staring at a package.json or a webhook payload that won't parse; or a build is failing on a config file and you suspect a stray comma. The validator catches the usual culprits — a trailing comma after the last item, single quotes instead of double quotes, an unquoted key, or a missing closing brace — and points you to the spot instead of just saying "invalid."

Beautify vs. minify

Beautifying adds the whitespace and line breaks that make JSON human-friendly. Minifying strips every unnecessary space and newline, shrinking the payload for storage or faster transfer — handy when you're pasting a config into an environment variable or trimming a request body. Both directions describe the exact same data; only the formatting changes, so you can round-trip freely.

How to use it

1. Paste or type your JSON into the input box — a full API response, a snippet, or a single object.
2. Click Format to pretty-print it with clean indentation, or Minify to collapse it to one compact line.
3. If something's off, read the error message; it names the problem and roughly where it sits so you can fix that character.
4. Copy the cleaned-up result back out and drop it into your code, config, or ticket.

FAQ

Does my data get uploaded anywhere?

No. The formatting and validation run entirely in your browser, so whatever you paste — including API keys or private payloads — never leaves your device.

Why does it reject JSON that looks fine?

Usually a trailing comma, single quotes, comments, or unquoted keys. Strict JSON requires double quotes on all keys and strings and allows no comments or trailing commas, even though many code editors are more forgiving.

Can it handle a large file?

Yes, big responses format fine since it all happens locally. Very deeply nested or multi-megabyte data may take a moment to render, but nothing is sent over the network.

Is it free?

Yes, completely free and supported by the ads on the page.