About this tool
What does it do?
It strips all insignificant whitespace from JSON, producing the smallest valid representation for storage and transfer — the inverse of prettify, with validation included.
How to use it
- Paste formatted JSON to compress it to one line.
- Validate first: errors are reported with positions.
- Copy the compact output into code, URLs or payloads.
Examples
- Shrinking a 48 KB pretty config to 31 KB for embedding.
- Preparing a JSON body for a curl command.
- Compressing fixtures to keep test repos small.
Important limitations
- Minifying never changes data — but it also never fixes semantic problems.
- Already-compact input returns nearly unchanged; savings come from whitespace.
- For transmission, gzip on top of minified JSON usually matters more than minification alone.
Privacy
Local transform. Payload contents stay in your browser.
Frequently asked questions
Minify or gzip?
Both: minify removes waste, gzip compresses patterns — they stack.
Does order change?
No — key order and values are preserved exactly.
Will it break my JSON?
No. Output is re-validated; invalid input is rejected, not mangled.