CSS Unit Converter
Convert between px, rem, em, vh, vw, and pt CSS units.
About the CSS Unit Converter
Convert between px, rem, em, vh, and vw CSS units. Essential tool for responsive web design.
Private by design
Everything you type here is processed inside your browser. Nothing is sent to a server, logged or stored, so it is safe to use with real numbers, drafts and anything you would not paste into a hosted tool.
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Questions people ask
How do I convert px to rem?
Enter the pixel value and the base font size (default 16px). The tool instantly calculates the equivalent rem, em, vh, and vw values.
What is the difference between rem and em?
rem is relative to the root element's font size, while em is relative to the parent element's font size. rem is generally preferred for consistent sizing.
Why should I use rem instead of px?
rem units respect the user's browser font size settings, making your site more accessible. They also make responsive design easier to manage.