Remove Unused CSS
Free · No Build Step · Processed in Your Browser
Paste your HTML and CSS. This checks every selector against your markup and flags rules that don't match anything — no install, no build tool, nothing uploaded.
Step 1a - Paste Your HTML
Step 1b - Paste Your CSS
Load an example · Processed in your browser — nothing you paste is uploaded.
Tip: press ⌘/Ctrl+Enter from either field to check.
Step 2 - Click Button
Used CSS
Matched at least one element in your HTML — kept as-is.
Possibly Unused CSS
Matched nothing in your HTML. Review before deleting — classes added by JavaScript won't show up here. See the FAQ below.
How Matching Works
- Each rule's selector list is tested against your HTML with the browser's own selector engine — not a guess or a text search.
- A comma-separated selector list (like
.btn, .alert) is kept whole if any part matches, so it's never split apart. - Interactive pseudo-classes (
:hover,:focus, etc.) are stripped before testing, since static HTML can't be "in" that state. @media,@font-face,@keyframes, and other at-rules are always kept — not evaluated.
This flags candidates for removal. It doesn't delete anything automatically — classes toggled by JavaScript at runtime won't appear in a static HTML paste, so always review the "possibly unused" column before acting on it.