What is a PX to REM Converter?
rem units respect the user’s font-size preference: the accessibility reason design systems specify type and spacing in rem while designers hand off pixels.
Convert any pixel value at any root size, with the common-values table you will otherwise re-derive weekly.
Frequently asked questions
Why rem instead of px?
Users who raise their browser font size get proportionally larger text and spacing with rem; px ignores their preference.
rem vs em?
rem is relative to the root (predictable); em is relative to the parent (compounds down the tree). Default to rem.
What is the 62.5% trick?
Setting html{font-size:62.5%} makes 1rem = 10px for easy math: at the cost of surprising every third-party stylesheet. Most teams skip it now.
Should borders be rem too?
Hairline borders usually stay px on purpose: you rarely want a 1px border scaling.