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PX to REM/EM converter
Convert between pixels, rem, and em with any base font size. Includes a Tailwind-style scale.
Common scale
Frequently asked questions
What is the difference between rem and em?
rem is relative to the root font size. em is relative to the parent element font size, so it can cascade.
Why is the default base 16?
Browsers default to 16px for the root font size unless overridden. Many design systems keep this default so user accessibility settings still apply.
How does this help responsive design?
Using rem lets the entire UI scale when a user adjusts their browser font size, improving accessibility and zoom behavior.