JSON formatter
FormattingPretty-print, minify, and validate JSON.
What this tool helps with
A JSON formatter does three jobs: pretty-print so a minified blob becomes readable, minify so a readable file becomes compact for transport, and validate so you find the exact position of a syntax error. This tool parses with the browser's own JSON engine, so what it accepts is exactly what your runtime will accept — no permissive superset that hides bugs. Large API responses, log lines, and config files are handled in-page; nothing is sent anywhere, so production payloads are safe to paste.
How to use JSON formatter
- Open the JSON formatter page and paste, type, or generate the json input you want to work with.
- Pick the options you need so the tool can pretty-print, minify, and validate JSON
- Copy the format result with one click and use it in your next step — terminal, editor, ticket, or anywhere else you need it.
Common uses
- Reach for JSON formatter when you need to pretty-print, minify, and validate JSON during debugging, code review, or content preparation.
- Skip installing a desktop json app — open this formatting utility on a shared machine, an iPad, or a colleague's laptop and it just works.
- Bookmark or share the page when you and your team keep coming back to the same json, format, pretty, and minify workflow.
FAQ
Why does my JSON fail to parse?
The usual causes are trailing commas, single quotes instead of double, unquoted keys, comments, or a stray BOM/character at the start. Strict JSON allows none of those. The error points at the offending position.
Does formatting change my data?
No. Pretty-printing and minifying only change whitespace. Key order is preserved as written. Numbers are not reformatted beyond what the JSON spec requires.
Can it handle very large files?
It parses in the browser, so the practical limit is your tab's memory rather than an upload cap. Multi-megabyte responses are fine; tens of megabytes may get sluggish.
Will big integers lose precision?
JavaScript's JSON.parse uses doubles, so integers beyond 2^53 lose precision — that is a property of JSON in JS, not this tool. If you need exact large IDs, keep them as strings in the source.