📐 Pixels to REM/EM Converter
Convert between absolute and relative CSS units
📌 Difference between units
- px: absolute fixed unit
- rem: relative to root font size (1rem = 16px default)
- em: relative to parent element font size
Pixels to REM and EM Converter
This converter helps web designers and front-end developers translate fixed pixel values into the relative units rem and em. Relative units scale with the user font size, which makes layouts more flexible, accessible and responsive across phones, tablets and large screens. Instead of hard-coding everything in pixels, you can express sizes in a way that respects the visitor browser settings.
The math is based on a root font size, which is 16px by default in most browsers. A value in rem is the pixel value divided by that root size, so 16px equals 1rem and 24px equals 1.5rem. The em unit works similarly but is relative to the font size of the current element rather than the root.
How to use it
Enter a pixel value and, if needed, adjust the base font size to match your project. The tool instantly shows the equivalent rem and em values you can paste straight into your CSS. This is useful for typography scales, spacing, margins and media queries. Using rem for font sizes keeps text readable when a user increases their default size, while em is handy for spacing that should grow with its component.