JSON Minifier
A free, instant JSON Minifier. Paste your JSON to minify it right in your browser — your data never leaves your device.
More presets
Jump to another preset — each opens its own page ready to go:
How to use the JSON Minifier
- Paste or type your JSON into the box.
- The result updates live — switch between Beautify, Minify and Validate any time.
- Copy the output, or read the line-and-column error if the JSON is invalid.
About the JSON Minifier
This JSON Minifier runs on the browser’s native JSON engine, so it accepts exactly what every other JSON parser does and reports the first syntax error with its line and column. Beautifying re-indents JSON for readability; minifying strips whitespace for the smallest payload; validating just confirms the structure is sound.
Everything happens locally — there is no upload, no account and no size cap beyond your device’s memory — so it is safe to use on private API responses, config files or production data. Use the indent and sort-keys options to produce stable, diff-friendly output. Note that numbers are parsed as native doubles, so integers above 2^53 or very long decimals may lose precision.
Frequently asked questions
Is my JSON uploaded?
No. The JSON Minifier works entirely in your browser, so your JSON never leaves your device.
Does it report errors?
Yes — invalid JSON is flagged with the exact line and column of the first problem, such as a trailing comma or a missing bracket.
Can I beautify and minify here too?
Yes. This tool does all three — Beautify, Minify and Validate — and you can switch between them with the buttons above the box at any time.
Is it free?
Completely. Format, validate and minify as much JSON as you like, free and in-browser.