Free tool
PX to REM Converter
Convert pixels to rem and back using any root font size. Type a value to convert instantly, or scan the reference table for common sizes.
Root font sizepx (default 16)
Pixels
px
⇄
REM
rem
Quick reference (base 16px)
4px0.25rem
8px0.5rem
12px0.75rem
14px0.875rem
16px1rem
18px1.125rem
20px1.25rem
24px1.5rem
32px2rem
40px2.5rem
48px3rem
64px4rem
FAQ
What is the default root font size?
Browsers default to 16px, so 1rem = 16px unless you change the root font size. You can adjust the base above to match your project.
Should I use rem or px?
rem scales with the user's browser font-size setting, which is better for accessibility. Many teams use rem for typography and spacing, and px for fine borders.
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