Accessing CSS Classes in FastHTML

by Audrey M. Roy Greenfeld | Fri, May 9, 2025

How to retrieve the CSS classes for a FastHTML FastTag instance.

from fasthtml.common import *

Define a Div in FastHTML, With Tailwind Classes

Here's a typical div with several Tailwind CSS classes:

d = Div(cls="container mx-auto p-4 bg-white dark:bg-gray-800")

d

Get the CSS Classes

The FT variable d has these attrs:

d.attrs

To get the CSS classes, you get the class attribute of d:

d.attrs['class']

Parse Them Into a List

Then you can split the space-separated string into a list, if you like:

css_classes = d.attrs['class'].split()
css_classes