CSS Unit Converter
Convert between CSS units with configurable base font size
Settings
Converted Values
px
—
rem
—
em
—
vw
—
vh
—
%
—
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CSS Unit Converter: px, rem, em, and More
Convert between CSS units and understand when to use px, rem, em, vw, and vh.
What Are CSS Units?
CSS units define the size of elements on a web page. They fall into two categories: absolute units (px, cm, mm, in, pt, pc) that have fixed physical sizes, and relative units (rem, em, vw, vh, vmin, vmax, %) that scale based on context like font size or viewport dimensions.
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