What is CSS Unit Conversion?
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Different units serve different purposes: px for fixed sizes, rem for scalable typography, em for relative spacing, and vh/vw for viewport-relative dimensions. Understanding these conversions ensures design consistency and accessibility.
Common Use Cases
- Converting a pixel design mockup to rem-based units for better accessibility and responsiveness across different screen sizes.
- Calculating font sizes and line heights when switching from a 16px to 18px root font size.
- Converting point sizes from print designs (pt) to web units (px/rem) when adapting print materials for the web.
- Working with viewport units (vh/vw) to create fluid layouts that scale with screen dimensions.
How CSS Unit Conversion Works
The converter takes your input value and unit, then calculates equivalent values across all supported CSS units. It uses standard conversion factors: 1rem = base font size (default 16px), 1em = parent font size, 1pt = 4/3px, 1cm = 37.795px, and 1in = 96px. You can adjust the base REM size to match your project's root font size.
Privacy & Security
All CSS unit conversions are performed entirely in your browser. No values are sent to external servers, ensuring your design specifications and calculations remain private.