JavaScript Minifier

What is a JavaScript Minifier?

A JavaScript minifier reduces the size of your code by removing whitespace and comments, shortening (mangling) variable and function names, and stripping unreachable dead code — all while preserving exactly how the program behaves. Smaller JavaScript downloads and parses faster, improving load time.

This tool is powered by Terser, the same compressor used by Webpack, Vite, and most modern build tools. Unlike naive find-and-replace minifiers that can corrupt strings, regular expressions, or template literals, Terser fully parses your code into a syntax tree, so the minified output is guaranteed to be functionally equivalent.

How to Minify JavaScript

• Paste your JavaScript, or click Sample to load an example
• Minification runs automatically using Terser with compression and name mangling
• The compact output appears in the right-hand pane
• If the code has a syntax error, a clear message tells you what went wrong
• Click Copy to copy the minified code to your clipboard

Why Minify JavaScript?

JavaScript is often the largest asset on a page, and its size directly impacts how quickly a site becomes interactive. Minification can cut file size dramatically — frequently by half or more — by removing everything that exists purely for human readability.

Combined with mangling and dead-code elimination, minification produces the lean bundles that production sites ship. This tool lets you minify a snippet on demand without setting up a full build pipeline.

Safe, Private, and Accurate

Because Terser runs entirely in your browser, your source code is never uploaded anywhere. And because it parses your code properly rather than guessing, you can trust that the minified output behaves identically to the original — strings, regexes, and template literals are all preserved correctly.