Minify JavaScript online by removing comments and whitespace and shortening syntax, cutting file size without breaking your code.
The engine parses your source into an AST with Terser, then emits compact JavaScript. Strip comments and whitespace in basic mode; advanced compression can fold constants and drop proven-unreachable code. It does not bundle npm packages, resolve imports, transpile TypeScript/JSX, or execute your script.
A successful minify means Terser could parse and print the program. That is not the same as running the file in Node.js or V8. Code can minify cleanly and still throw at runtime, and some syntax (JSX, TypeScript) is rejected because it is not plain JavaScript.
Basic compression keeps statement structure and only compacts formatting. Advanced compression is opt-in: Terser may rewrite equivalent expressions, remove dead branches it can prove unused, and drop debugger/console calls if you enable those checkboxes. Console removal can change behavior if you rely on console side effects.
Local mangling renames function-scoped bindings only. Top-level and exported names are left intact so pasted snippets and modules keep their public API. Global/toplevel mangling is not offered because it is easy to break scripts that other files depend on.
Parsing and minification run in your browser. Source is never eval’d. Companion tools include the <a href="/json-formatter" class="text-brandBlue-400 hover:underline font-semibold">JSON Formatter</a>, <a href="/css-minifier" class="text-brandBlue-400 hover:underline font-semibold">CSS Formatter & Minifier</a>, <a href="/html-formatter" class="text-brandBlue-400 hover:underline font-semibold">HTML Formatter</a>, and <a href="/sql-formatter" class="text-brandBlue-400 hover:underline font-semibold">SQL Formatter</a>.
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