JavaScript Minifier
Compress JavaScript with dead-code removal and variable renaming to reduce bundle size.
How it works
- 1
Paste your JavaScript source into the input area.
- 2
Press Minify JavaScript — terser compresses the code in your browser.
- 3
Download the minified file or copy the output. Nothing is sent to any server.
Questions
What optimisations does the minifier apply?
It uses terser to remove dead code, shorten variable names, and strip whitespace and comments. The result is semantically identical to the original.
Will it break my code?
Terser is widely used in production build pipelines and is generally safe. If your code uses non-standard syntax it may not parse correctly — the tool will show the error message.
Is my JavaScript processed on a server?
No. Terser runs entirely in your browser as a WebAssembly bundle — your source code never leaves your device.
Should I minify already-minified code?
Running the minifier a second time usually makes no difference. Start from the readable source for the best reduction.
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