JSON Formatter

Beautify, validate and minify JSON online with precise error messages. Syntax-highlighted output — processed locally.

Runs entirely in your browser — no uploads

About this tool

JSON Formatter validates your JSON and pinpoints the exact line and column of syntax errors, then pretty-prints with 2-space indentation or minifies to a single compact line.

Your data never leaves the browser — important for API responses, tokens or config snippets that shouldn’t touch third-party servers.

Free · no account No file uploads Works on mobile

FAQ

What does the error message show?
The parser reports the first error with its line number, column and a human-readable reason — far easier than hunting brackets manually.
Can I sort object keys alphabetically?
Yes — tick “Sort keys” before formatting to recursively sort every object’s keys.
Is my JSON logged anywhere?
Never. Parsing and printing happen in JavaScript on your device; there is no network call.