Free browser tool
Format, validate, and minify JSON without uploading it
Pretty-print, validate, and minify JSON in your browser. Catch syntax errors by line and path, inspect a tree, then copy or download the result. Built for daily debugging and safe to use with private payloads.
JSON workbench
Format with Ctrl/⌘ Enter. Minify with Ctrl/⌘ Shift Enter. Files never leave this tab.
How it works
Three steps. No account. No round trip.
- 01
Paste or drop
Drop a .json file onto the editor or paste from your clipboard. Nothing is stored on a server.
- 02
Format, minify, or validate
Pretty-print with 2 or 4 spaces, compress to one line, or check validity. Errors include line, column, and JSON path.
- 03
Copy or download
Copy the result, download formatted.json, or inspect the tree and key-count stats before you ship the payload.
FAQ
Straight answers for people comparing JSON formatters, linters, and minifiers.
No. Formatting, validation, and minification run entirely in your browser with the built-in JSON parser. This app does not send the document to a server. If you enable Google AdSense later, ad requests are separate from the editor and do not include your JSON.
Paste JSON into the editor or drop a .json file, then choose Format (or press Ctrl/⌘ Enter). The tool re-serializes valid JSON with 2- or 4-space indentation. Enable Sort keys if you want object keys in alphabetical order.
Minify removes insignificant whitespace so the payload is as small as JSON.stringify allows. Use it before embedding JSON in a URL, storing it, or comparing compact size. Minify still validates first — invalid JSON is not rewritten.
Common issues include trailing commas, single quotes, comments (JSONC), unquoted keys, and smart quotes from a word processor. The validator reports the engine message plus line, column, and an estimated JSON path such as $.user.address[0].
The formatter is free to use. Ad slots are reserved for Google AdSense and stay as labeled placeholders until you set NEXT_PUBLIC_ADSENSE_CLIENT and slot IDs. There are no fake publisher IDs and no extra analytics trackers in this codebase.
Yes. The editor, actions, and tree view are laid out for small screens. You can paste from the keyboard, upload a file, copy the result, or download formatted.json.
No. This tool validates strict JSON (ECMA-404 / RFC 8259). Comments, trailing commas, and unquoted keys will fail with a location. Convert those dialects to JSON before formatting if you need a standards-compliant document.