Production JavaScript should be small. This tool gets it there: minify js in your browser with terser, free, compressing and mangling so your script ships lighter. The whole minify step stays on your device.
Same behavior, fewer bytes.
Source JavaScript is written for humans, with long names, spacing, and comments. To minify js is to hand it to terser, which compresses the code and mangles variable names into short ones, leaving a tight block that behaves exactly the same. The result is what javascript minify is after: smaller files that load and parse faster.
People reach it as minify js online or javascript minify online, and sometimes just search minify. However it is phrased, the tool runs terser locally in your browser, so even private code stays on your machine.
Minifying is one direction.
Minified JavaScript is hard to read because the names are shortened, so it is effectively one-way for legibility. The JS Beautifier can re-indent it if you need to inspect the structure, though the mangled names stay as they are.
CSS has its own minifier. For minify css online, use the CSS Minifier rather than this page, and run each language through its own tool so the output stays valid.
Stop reading. Start using.
That is everything worth saying. Open the tool and try it on something real. You will know within a minute whether it belongs in your kit.
If you found this useful, the other Developer guides are written in the same voice. We keep them short, practical, and rooted in real work.
mytoolstudio is designed and built by the team at GAP3, a small studio that ships product, brand, and growth work for early stage companies. We built this site as a free public good. Read more about us at gap3.co.
Try it now
The tool is one click away. No sign up, no upload, no payment.
Open JS Minifier