PX to REM Converter

Design Tools

Convert pixels to rem and em for CSS

FreePrivateInstant
Convert
Value
Root font size (px)
Full guide, 3 min readpx vs rem: why your font sizes should be allowed to scaleRead the story behind this tool →

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History

All history →

PX to REM Converter — at a glance

Convert pixel sizes to rem and em units (or back) based on your root font size.

Your values
24px at 16px root
Run
Result
1.5rem

How to use it — step by step

A pixel or rem value and your root font size.

1

Enter your values

Fill in the boxes. Sample values are already there so you can see how it works.

2

Calculate

Press the button to get your answer instantly.

3

Read the result

The main answer is shown in a large card with extra details below it.

4

Copy it

Use the copy button to save the result anywhere.

Pro tips

Small things that make the result better.

✦Browsers use 16px as the default root size.
✦rem units respect the user’s font-size setting.
✦em depends on the parent element’s size, rem on the root.

Quick facts

Freeno signup, no limit
Instantresult in a moment
Privatenothing is uploaded
Any devicephone, tablet or PC

Frequently Asked Questions

Why use rem instead of px?+

rem scales with the user’s browser font settings, which is better for accessibility.

Is my data safe?+

Yes. Everything runs inside your own browser. Your text, files and images are never uploaded to any server.

Is this tool really free?+

Yes — completely free, no signup, no watermark and no usage limit.

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