JSON Tool 01

Format, validate & compress JSON

Format, validate and minify JSON without uploading it. Drop a .json file up to 15 MB or paste text — parsing happens in your browser, so the document never leaves your machine.

Input Paste JSON to begin
Load example

Paste JSON here

or press Ctrl V — nothing leaves your browser
Result Formatted JSON

Result appears here

Format, minify, escape or validate — the input stays intact
Ready 0 lines · 0 chars Result — Ctrl ↵ format · drop a .json file to load 100% client-side

Frequently asked

How large a JSON file can it handle?
Dropped .json files up to 15 MB are read and formatted locally. Pasted text has no fixed limit beyond the memory the browser gives the tab. Either way the document is parsed in the page, never uploaded.
Is my JSON sent to a server?
No. Formatting, minifying and validation are plain JavaScript running in the page, and the tool scripts make no network requests. The only third-party request on the page is anonymous page-view analytics, which never receives editor content.
Does it still work if my connection drops?
Yes, once the page has loaded. There is no server round-trip to lose, so formatting continues while offline.
Does it handle minified or escaped JSON?
Yes. Format, Minify, Escape and Unescape act on the same document, and the result never overwrites your input — input and result sit side by side.
Is my last document stored anywhere?
The formatter remembers your last input in this browser's local storage so a reload does not lose it. It stays on your machine and clearing site data removes it.