An HTML Minifier with Seatbelts

htmlin is an HTML minifier that just works. It comes with safe defaults and an easily configurable set options. It cam turn this:

    <title>  Hello, World!  </title>
    <p> How are <em>you</em> doing?  </p>

Into this:

<html><head><title>Hello, World!</title><body><p> How are <em>you</em> doing? </p></body></html>

When we say that htmlmin has ‘seatbelts’, what we mean is that it comes with features that you can use to safely minify beyond the defaults, but you have to put them in yourself. For instance, by default, htmlmin will never minimize the content between <pre>, <textarea>, <script>, and <style> tags. You can also explicitly tell it to not minify additional tags either globally by name or by adding the custom pre attribute to a tag in your HTML. htmlmin will remove the pre attributes as it parses your HTML automatically.

It also includes a command-line tool for easy invocation and integration with existing workflows.


To install via pip:

pip install htmlmin

Source Code

Source code is availble on github at

git clone git://


  • Safely minify HTML with either a function call or from the command line.
  • Extend what elements can and cannot be minified.
  • Intelligently remove whitespace completely or reduce to single spaces.
  • Properly handles unclosed HTML5 tags.
  • Optionally remove comments while marking some comments to keep.
  • Simple function decorator to minify all function output.
  • Simple WSGI middleware to minify web app output.
  • Tested in both Python 2.7 and 3.2: build_status

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