PX to REM & CSS Unit Converter
Convert between Pixels (px), REM, EM, Percent (%), and Viewport units (vw, vh) with customizable base font size.
100% Private & Client-Side
Your files are processed directly on your computer or phone. They are never uploaded to any remote server or stored anywhere.
How to use PX to REM & CSS Unit Converter
Enter a value and select your starting unit (e.g. 24px).
Set your root font size (default 16px).
Copy the exact converted REM, EM, or Viewport values into your stylesheet.
Frequently Asked Questions
Why should I use REM instead of PX in CSS?
REM (root EM) scales relative to the user's browser default font size (typically 16px). This ensures your web design respects user accessibility preferences when they zoom or change browser font scales.
Can I customize the base root pixel size?
Yes, while the standard web default is 16px, you can easily adjust the base to 10px (62.5% trick) or any custom project baseline.
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