rem to px Calculator
A free, browser-based calculator. Runs entirely in your browser — no sign up, nothing stored.
100% FreeRuns in your browserBasic
Enter Values
Enter your values and press Calculate to see results.
How to use this calculator
- Enter a value in rem or px.
- Set the root font size if it isn't 16 px.
How it works
px = rem × root font size; rem = px ÷ root font size.
Worked example
1.5 rem at 16 px root. = 24 px.
Common mistakes
- Forgetting the user's root size may differ from 16 px.
- Confusing rem (root-relative) with em (parent-relative).
Frequently asked questions
Why use rem over px?
rem scales with the user's chosen base font size, which is better for accessibility.
Related tools
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.