Developer Tool

PX to REM Converter

Instantly convert pixels to REM or EM units for perfectly responsive CSS styling.

Base Font Size: px
PX
⇄
REM
EM

How does this work?

REM (Root EM) and EM are relative units used in CSS to ensure designs scale properly across different devices and user settings. The conversion is based on the root/base font size of the document (typically 16px in most modern browsers).

  • REM is relative to the root `html` font-size.
  • EM is relative to the font-size of the element's parent.