JSON Minifier
Minify JSON online for free — remove all unnecessary whitespace and see exactly how much smaller it got. Nothing uploaded to a server.
Your files are processed locally in your browser and are not uploaded to our servers.
How to use JSON Minifier
- 1
Paste your JSON into the box.
- 2
Click "Minify."
- 3
See the original size, minified size, and percentage reduction.
- 4
Copy or download the result.
Common uses
- Shrinking JSON before pasting it somewhere with a character or size limit
- Preparing a compact JSON payload for a URL parameter or config value
- Seeing exactly how much of a JSON file's size was just formatting whitespace
Supported formats and limitations
Accepts JSON, up to one file at a time.
- Minifying only removes whitespace — it doesn't shorten key names or restructure the data, since that would change what the JSON actually represents.
- Invalid JSON is rejected with a clear error rather than producing an incorrect minified result.
Frequently asked questions
No. Minifying happens entirely in your browser.
It compares the original character count to the minified character count — a genuine, measured reduction, not an estimate.
You'll see a clear error message instead of an incorrect or empty result.
No — only whitespace is removed. Every key, value, and structure stays exactly the same.