PX to REM Converter – CSS Pixel & REM Calculator

ToolsFaction Online Tool

PX to REM Converter

Convert CSS pixels and REM units with a custom root size.

Convert CSS pixels to REM units and REM back to pixels using a custom root font size.

About This Tool

ToolsFaction PX to REM Converter calculates CSS length values using the selected root font size. It supports both PX-to-REM and REM-to-PX conversion for responsive design systems and frontend development.

How to Use

  1. Enter a pixel or REM value.
  2. Set the root font size used by the page.
  3. Choose PX to REM or REM to PX.
  4. Use the converted CSS value in your design.

Example

At a 16 px root font size, convert 24 px to 1.5 rem.

Frequently Asked Questions

What is REM based on?

REM units are relative to the root element font size.

Can I change the root font size?

Yes.

Can it convert both directions?

Yes. PX to REM and REM to PX are included.

Does this modify website CSS?

No. It only calculates values.

Free to UseNo hidden fees
No Sign-UpStart instantly
Browser-BasedNothing to install
Privacy FriendlyBuilt for simple use
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