CSS Duplicate Checker Tool
Check your CSS code for duplicates and issues using one of the three input methods below.
The tool checks for duplicate classes, IDs, tags, pseudo-elements, empty declarations, and duplicate media queries.
CSS Input Options
CSS Analysis Results
What This Tool Checks For
- Duplicate class and ID selectors (.class, #id)
- Duplicate tag selectors (div, span, p, etc.)
- Duplicate pseudo-elements (:before, :after) and pseudo-classes (:hover, :focus, etc.)
- Empty declarations (selectors with no properties or values)
- Duplicate media query definitions (@media with the same query)
- Invalid or potentially problematic CSS patterns