Skip to main content

JavaScript minifier.

Project description

JavaScript minifier.


from jsmin import jsmin
with open('myfile.js') as js_file:
    minified = jsmin(

You can run it as a commandline tool also:

python -m jsmin myfile.js

NB: jsmin makes no attempt to be compatible with ECMAScript 6 / / Harmony. The current maintainer does not intend to add ES6-compatibility. If you would like to take over maintenance and update jsmin for ES6, please contact Tikitu de Jager. Pull requests are also welcome, of course, but my time to review them is somewhat limited these days.

If you’re using jsmin on ES6 code, though, you might find the quote_chars parameter useful:

from jsmin import jsmin
with open('myfile.js') as js_file:
    minified = jsmin(, quote_chars="'\"`")

Where to get it

Python 2 support removed

Python 2 support was removed in version 3.0.0. If you need to support Python 2, please use version 2.2.2 with setuptools<58.


Issues and Pull requests will be gratefully received on Github. The project used to be hosted on bitbucket and old issues can still be found there.

If possible, please make separate pull requests for tests and for code: tests will be added to the latest-release branch while code will go to master.

Unless you request otherwise, your Github identity will be added to the contributor’s list below; if you prefer a different name feel free to add it in your pull request instead. (If you prefer not to be mentioned you’ll have to let the maintainer know somehow.)

Build/test status

Both branches are tested with Travis:

The latest-release branch (the version on PyPI plus any new tests) is tested against CPython 3. Currently:

If that branch is failing that means there’s a new test that fails on the latest released version on pypi, with no fix yet released.

The master branch (development version, might be ahead of latest released version) is tested against CPython 3. Currently:

If master is failing don’t use it, but as long as latest-release is passing the pypi release should be ok.

Contributors (chronological commit order)


v3.0.0 (2021-09-08) Ben Bradshaw

  • Breaking Change: Removed support for Python 2

  • Removed usage of use_2to3 in

v2.2.2 (2017-05-01) Tikitu de Jager

  • Add license headers to code files (fixes i#17)

  • Remove mercurial files (fixes #20)

v2.2.1 (2016-03-06) Tikitu de Jager

  • Fix #14: Infinite loop on return x / 1;

v2.2.0 (2015-12-19) Tikitu de Jager

  • Merge #13: Preserve “loud comments” starting with /*!

    These are commonly used for copyright notices, and are preserved by various other minifiers (e.g. YUI Compressor).

v2.1.6 (2015-10-14) Tikitu de Jager

  • Fix #12: Newline following a regex literal should not be elided.

v2.1.5 (2015-10-11) Tikitu de Jager

  • Fix #9: Premature end of statement caused by multi-line comment not adding newline.

  • Fix #10: Removing multiline comment separating tokens must leave a space.

  • Refactor comment handling for maintainability.

v2.1.4 (2015-08-23) Tikitu de Jager

  • Fix #6: regex literal matching comment was not correctly matched.

  • Refactor regex literal handling for robustness.

v2.1.3 (2015-08-09) Tikitu de Jager

  • Reset issue numbering: issues live in github from now on.

  • Fix #1: regex literal was not recognised when occurring directly after {.

v2.1.2 (2015-07-12) Tikitu de Jager

  • Issue numbers here and below refer to the bitbucket repository.

  • Fix #17: bug when JS starts with comment then literal regex.

v2.1.1 (2015-02-14) Tikitu de Jager

  • Fix #16: bug returning a literal regex containing escaped forward-slashes.

v2.1.0 (2014-12-24) Tikitu de Jager

  • First changelog entries; see README.rst for prior contributors.

  • Expose quote_chars parameter to provide just enough unofficial Harmony support to be useful.

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

jsmin-3.0.1.tar.gz (13.9 kB view hashes)

Uploaded source

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page