CSS Unit Converter px rem em pt
Convert CSS units (px, rem, em, pt) with a configurable base.
🔒 100% client-side — no data sent
Instantly convert CSS units between px, rem, em and pt with a customizable base (root font-size). Perfect for moving from pixels to responsive values without manual math. Everything runs in your browser: no data is ever sent to a server.
What is it for?
- ▸ Convert px mockups to rem
- ▸ Set a 16px base and see values recalculated
- ▸ Switch from pt (print) to px for the web
- ▸ Harmonize em/rem units across a stylesheet
FAQ
What is the default base for rem?
16px, the browser's default root font-size. You can change it.
What's the difference between em and rem?
rem refers to the root, while em depends on the parent's font-size (can compound).
Is data sent?
No, everything is local to your browser.
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