The JSON formatter takes minified, messy or hand-edited JSON and pretty-prints it into clean, indented, readable text. Paste an API response, a config file or a log line and it beautifies the structure instantly so you can actually see the objects, arrays and nesting you are working with.
It runs entirely in your browser. Nothing you paste is uploaded, logged or sent to a server — the formatting happens in JavaScript on your own machine, so it is safe for production payloads, tokens and customer data. Turn off your network and it still works.
It is built for developers, data engineers, QA testers and anyone who reads JSON all day: quickly reformat a payload from the network tab, tidy a config before committing, or collapse everything back down with the minify toggle. Free forever, no signup, no file-size gate.
Pick 2 spaces (the most common default), 4 spaces, or tab indentation. The choice re-renders the output immediately. Two-space indentation keeps diffs small and matches Prettier and most linters; tabs suit teams that indent with tabs everywhere else.
Flip the Minify switch to strip every non-essential space and newline, producing the smallest valid payload on a single line. This is the exact output you want to ship over the wire or embed in a request body, and it round-trips losslessly back to the pretty view.
The formatter parses with the browser's native JSON engine, so it is strict RFC 8259: no comments, no trailing commas, no single quotes. If the input is invalid you get the error message plus the line and column of the first problem instead of a silent blank output.
Formatting never reorders your keys or changes values. Numbers, booleans, null and strings come out exactly as they went in — only whitespace changes. Unicode escapes inside strings are left intact so nothing is lost in the round trip.
Yes. All formatting happens locally in your browser with JavaScript — the JSON is never uploaded or sent anywhere. You can even disconnect from the internet and the tool keeps working.
Two spaces is the safest default: it matches Prettier, most linters and keeps version-control diffs compact. Use 4 spaces or tabs only if your project's style guide requires it.
The formatter uses strict RFC 8259 parsing, which rejects trailing commas, comments and single-quoted keys or strings. The error message points to the line and column of the first problem so you can fix it.
No. Only whitespace changes. Keys stay in their original order and every value — numbers, strings, booleans, null — is preserved exactly.
There is no artificial limit. Very large documents (tens of megabytes) depend on your device's memory since everything runs in the browser tab, but typical API responses and config files format instantly.