CSS Unit Converter
Convert between px, em, rem, %, pt, vh, vw for common design values — configurable 16 px base. Everything in your browser.
Convert CSS units
CSS has a soup of units: px, em, rem, %, pt, vh, vw, and each one makes sense in a different context. Knowing what one equals in another helps you build more flexible layouts. This converter handles that translation for the common design values.
Relative units depend on a base, usually 16 px, and here that reference is configurable to match your project. So you find out how many rem make up 24 px, or how a measurement turns into viewport units, without doing division in your head on every tweak.
The calculation runs in the browser. A practical reference for web developers who keep moving between fixed and relative units all day.
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