CSS Units Converter
Convert CSS units online - transform between px, rem, em, vh, vw, and percentage values with live preview
Unit Converter
Live Preview
Actual size: 16px
CSS Unit Types
Absolute Units
px, pt, pc, in, cm, mm
Relative Units
rem, em, %
Viewport Units
vh, vw
Recent Conversions
About CSS Unit Conversion
Understanding CSS Units
CSS units are essential for defining sizes, spacing, and positioning in web design. This converter helps you translate between different unit types with context awareness.
Absolute Units
Fixed physical measurements (px, pt, in, cm, mm, pc) that don't change based on context.
Relative Units
Units relative to other elements (rem, em, %) that scale based on parent or root font size.
Viewport Units
Units relative to the viewport size (vh, vw) for responsive design.
Features
- • Context Aware: Configure base font size and viewport dimensions
- • Live Preview: See actual rendered sizes
- • Comprehensive: Support for all major CSS units
- • History: Track recent conversions
- • Copy Values: One-click copying of results
Pro Tips
- • Use rem for scalable typography
- • Use vh/vw for full-viewport layouts
- • Configure base font size to match your project
- • Use % for relative sizing within containers