What is Px to Rem & Rem to Px Calculator?
Px to Rem Calculator converts pixel (px) values to relative rem and em CSS units based on a configurable root font size (default 16px). Using relative rem units instead of fixed pixels is critical for modern responsive web design and accessibility.
How to use Px to Rem & Rem to Px Calculator
Enter pixel values to output corresponding rem values instantly, or enter rem values to convert back to pixels. Adjust root font size (default 16px).
Key features
- Bi-directional Px <-> Rem conversion
- Configurable root font size (default 16px)
- Generates CSS code snippets
- 100% client-side operation
Common use cases
- Converting Figma/Adobe XD design pixel specs into responsive CSS rem code
Technical details & standards
Calculates rem = px / rootFontSize client-side.
Frequently asked questions
Why should I use rem instead of px in CSS?
rem units scale dynamically when users adjust browser default font size settings, significantly improving web accessibility.
Is my data safe?
All processing happens entirely in your browser. Your data never leaves your device and is never sent to or stored on a server.
Does it work offline?
Yes. Once the page has loaded, most tools keep working without an internet connection.