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Minify JavaScript

Shorten JavaScript source while keeping licence comments intact. Files stay on your device.

How this works locally
  1. You choose a file; the page reads it from your device.
  2. The matching engine is loaded from fileslimmer.com and runs in a Web Worker.
  3. The result is written back to a location you choose on this device.

Before or choose files from your device

Original size —

Accepted formats
Reads
JS · MJS

The output keeps the language it was written in; only the text is rewritten.

Estimated memory

Your browser reports only a coarse memory hint, so this figure is an estimate.

Input budgets for this tool
LimitValue
File size20 MiB

These budgets protect the tab from a file that expands far beyond its stored size (spec 9.3). They do not vary by device, because parsing text is bounded by the text itself.

Limitations
  • Your file is parsed and rewritten as text and is never executed. Minified output is equivalent only when the source parses; a syntax error stops the task instead of guessing.
  • Licence comments are kept in the output, so an attribution requirement in the source survives minification.
  • Renaming identifiers breaks code that looks a name up as a string, and a stack trace from the output no longer matches your source.