CSS Unit Converter
Convert between CSS units: px, rem, em, pt, vw, vh, cm, mm, and inches.
CSS Unit Converter
px
16
rem
1
em
1
pt
12
vw
1.1111
vh
1.7778
cm
0.4233
mm
4.2333
in
0.1667
Why CSS Unit Conversion Matters
Modern responsive web design uses a mix of absolute (px, pt, cm) and relative (rem, em, vw, vh) units. Accurate conversion between them — especially relative units like rem and vw which depend on base font size and viewport — is critical for responsive layouts.