Minify JSON — strip whitespace for smaller payloads
Paste formatted JSON and get the smallest valid equivalent, with a count of bytes saved. It runs in your browser (0 uploads, works offline).
How to use it
- Paste your input into the left pane.
- Choose any options shown above the panes.
- The result updates live on the right — Copy or Download it.
FAQ
How do I minify JSON online for free?
Paste your JSON and it is re-serialised with no spaces or line breaks, in your browser, with no upload — and the tool shows how many bytes you saved. Invalid JSON gives a clear error rather than mangled output.
Does minifying change my data?
No — only whitespace is removed. The parsed value is identical, so a minified document and its formatted original mean exactly the same thing to any JSON consumer.
Is my JSON uploaded?
No. Minification is local and nothing is stored; it works offline.
When should I minify JSON?
For payloads sent over the network or embedded in code, where every byte counts. For files a human reads, keep them formatted.
Limits
Works on valid JSON only; invalid input is reported rather than guessed at. Key order is preserved.
Related
The JSON formatter does the reverse — pretty-printing and validating.
Bookmark this page (Ctrl+D, or ⌘D on Mac) or install the app — it works offline the next time you need it.