CSS Unit Converter
Convert between CSS units: pixels, ems, rems, percentages, viewport units, and more.
1remQuick Reference (base: 16px)
8px = 0.5rem
12px = 0.75rem
14px = 0.875rem
16px = 1rem
18px = 1.125rem
20px = 1.25rem
24px = 1.5rem
32px = 2rem
Features
- 10 unit types
- Custom base font
- Custom viewport
- Instant conversion
- Swap function
- One-click copy
How to Use
- 1Enter a value
- 2Select units
- 3View result
- 4Copy the output
Frequently Asked Questions
What is the base font size?
Most browsers default to 16px. This is used for em/rem/% calculations.
When to use rem vs em?
Use rem for consistent sizing (relative to root), em for component-relative sizing.