Convert REM to PX
Sometimes you need the concrete pixel value behind a rem — to match a design spec, debug a layout, or document a component. This converter multiplies rem values by the root font size (16px by default) to give you the exact pixel equivalent.
0.5rem 1rem 1.5rem 2rem 3rem
8px 16px 24px 32px 48px
Try it with your own data
Frequently Asked Questions
What is the difference between REM and EM?
rem (Root EM) is relative to the root element (usually <html>) font size. em is relative to the font size of its nearest parent element.
Why use REM instead of Pixels?
Using rem units is crucial for accessibility. If a user changes their browser's default font size, your entire layout will scale proportionally, which is not possible with static pixel units.
How to convert REM to PX
- Take the rem value you want to convert.
- Multiply it by the root font size (16px in a default browser).
- The result is your value in pixels — e.g. 1.5rem × 16 = 24px.
Frequently asked questions
How many pixels is 1rem?
At the browser default root font size of 16px, 1rem equals 16px. 2rem equals 32px, and 0.5rem equals 8px.
Does rem to px change if the root font size changes?
Yes. Rem is relative to the :root (html) font size. If you set html { font-size: 20px } then 1rem becomes 20px. Adjust the base in the calculator to match.