Physics & Engineering

PX to REM Converter

rem = px / root px

Educational estimates only. Not medical, legal, tax, or financial advice.

Guide: PX to REM Converter

What it does

Divides target px by root px.

How to use it

Enter root font size and target pixels.

Formula

rem = target_px ÷ root_px.

Example

24 px with 16 px root → 1.5 rem.

FAQs

What about em?

em is relative to parent font; rem is relative to root—this tool outputs rem.

User zoom?

rem scales with root font size, helping accessibility when users zoom.

Root not 16px?

Always match the root font size your stylesheet sets on html.