Unit Converter

Convert PX, REM, EM, %

Default is usually 16px
px
rem
em
%

About CSS Unit Converter

1What is it?

Convert between Pixels (px), REM, EM, and Percentage (%) values. Essential for responsive web design and creating scalable layouts. Set your base font size for accurate conversions.

2Use Cases

  • Convert legacy pixel values to modern REM units
  • Calculate percentage widths for fluid layouts
  • Standardize typography scales
  • Debug layout issues related to font sizing
  • Create accessible, scalable user interfaces

3Examples

Convert 16px

Input

16px (Base 16)

Output

1rem
1em
100%

?Frequently Asked Questions

What is the difference between REM and EM?

REM (Root EM) is relative to the root element (html tag) font size. EM is relative to the font size of the parent element. REM is generally preferred for consistency.

Why use REM instead of PX?

REM units allow users to scale the entire website by changing their browser's default font size, making your site more accessible and responsive.