CSS Coverage Analyzer

Inspect pasted CSS for waste.

Runs in your browser. Nothing is uploaded — your input is processed on this device and discarded when you close the tab.

CSS code

How to use this tool

Enter your values in the fields above.
Press Generate to see the result.
Use Load sample to try the worked example, Copy result to copy it, or Clear to start again.

The sample has 4 rules and 4 selectors. Selector h1 appears twice, 1 rule is empty, and 0 declarations use the important flag.

This analyzes CSS text you paste. It does NOT scan a live site or know which selectors your pages actually use, so it cannot prove a rule is unused.

Does a duplicate selector mean waste?

Not always. Later rules can override earlier ones on purpose, but duplicates are worth checking.

Can this tell me which rules are unused?

No. That needs usage data from real pages. This tool only reports structure inside the pasted CSS.

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