JavaScript Formatter and Minifier
Format JavaScript or compact parsed script/module source without executing it.
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How to use JavaScript Formatter and Minifier
Format JavaScript or compact parsed script/module source without executing it. A declared ECMAScript2022 script or module is parsed before transformation. Format uses standalone Prettier; Minify uses Terser with compression and name mangling disabled, preserving license comments and program structure.
- Provide javascript source, indent spaces.
- Choose the supported mode and run the tool. Review its assumptions and any reported errors.
- Copy the result or download a separate output; reset to clear the current form.
Good to know
- 50,000 source characters;10 seconds to load the worker/libraries, then2 seconds to compute. The worker is terminated on success, failure or timeout.
- Output is untrusted source text: it is never executed or inserted into this page. No linked resources or source maps are fetched.
- ECMAScript2022 only. JSX, TypeScript, custom plugins, downlevel compilation, arbitrary options and code evaluation are unsupported. Script mode rejects module declarations.
- Minify is token-aware spacing/comment compaction, not aggressive compression. Names, console/debugger statements and top-level behavior are retained.
- Inputs are processed on this device and are not automatically saved or uploaded.
Common questions
Is the output run to check that it works?
No user source or generated source is executed. Syntax parsing and trusted semantic fixtures check the transformation; they do not prove every application behavior or compatibility with older JavaScript engines.
Does this change my original input?
No. The tool returns a separate result. Review that output before using it in another application.
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