JSON Minifier
Developer & DataStrip whitespace to compress JSON to the smallest valid form.
Options
JSON input
Minified JSON
0 characters in · 0 out. Processed entirely in your browser.
What is JSON Minifier?
JSON Minifier strips every unnecessary space, tab, and line break from your JSON, re-serializing it into the smallest valid form — perfect for shrinking config files, API payloads, and embedded data. It parses the input first, so you also get instant validation: malformed JSON shows a clear error instead of silently breaking. Flip to Prettify mode when you need the readable, indented version back. Everything runs in your browser, so your data is never uploaded.
How to use JSON Minifier
Paste your JSON
Drop raw or already-formatted JSON into the input box, or use Load file to open a .json file from your device. The result updates as you type.
Choose Minify or Prettify
Minify (the default) removes all insignificant whitespace for the most compact output. Prettify re-indents the same data with two spaces when you need it human-readable again.
Watch for validation errors
If the JSON is invalid, a red message explains what went wrong so you can fix the offending bracket, comma, or quote before minifying.
Check the size savings
The footer shows characters in versus out, so you can see exactly how much smaller the minified version is.
Copy or download
Use Copy to grab the result, or Download to save it as minified.json (or formatted.json in Prettify mode).
Common uses
- Shrink JSON config or data files before committing or shipping them
- Compress API request and response bodies to reduce payload size
- Inline JSON into a single-line environment variable or data attribute
- Validate that a snippet is well-formed JSON before using it
- Reformat minified JSON back into readable, indented text
- Prepare compact JSON for embedding in HTML, scripts, or QR codes
Why choose FreeTools
100% private
Your files are processed inside your browser and are never uploaded to a server.
Free, no account
No sign-up, no watermark, no paywalled “premium” tier. Just open a tool and use it.
Instant
No upload, no queue, no server round-trip — work starts the moment you drop a file.
Runs in your browser
Built on open web standards. Works on any modern desktop browser, nothing to install.
No upload size caps
Nothing leaves your device, so there’s no server file-size limit — only your machine’s memory.
Yours to keep
Results download straight to your device in clean, standard file formats.