Input JSON
Formatted Output
—
Size
—
Keys
—
Depth
—
Status
Format, validate, and minify JSON instantly. Free, private — nothing leaves your browser.
JSON is the lingua franca of APIs, and most of the time you meet it at its worst: minified into a single unreadable line inside a log file or a network tab. This formatter pretty-prints, validates, and minifies JSON entirely in your browser — which matters, because production API responses often contain tokens, emails, and customer data you should never paste into a random website.
When validation fails, it's nearly always one of these: a trailing comma after the last element (legal in JavaScript, illegal in JSON); single quotes instead of double quotes; unquoted keys; undefined, NaN or Infinity as values (none exist in JSON); or a raw newline inside a string that should be \n. The validator points at the offending line so you fix the actual problem instead of bisecting by hand.
Two-space indentation is the debugging default. Minifying strips whitespace for payloads and config files — typically a 20–30% size cut on structured data before gzip. If you're inspecting an API response, format it, read it, fix your code, then re-minify nothing: the copy on the wire was never modified.
Because parsing is local, multi-megabyte exports (database dumps, HAR files, analytics exports) format as fast as your machine allows — there's no upload progress bar and no server-side size cap.
7 Claude prompt systems — prompt engineering, cold outreach, launches, demos, SEO and more. The Complete Suite: all 7 for $297 (vs $679 apart). One-time, yours forever.
Explore the Complete Suite — $297 →