CSS Units Converter
Convert between px, rem, em, pt, %, vw, and vh.
🔒 All conversions happen in your browser.
How to Use CSS Units Converter
1
Enter a value and select the unit
2
Adjust base font size if needed
3
Click any result to copy it
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About CSS Units
CSS supports multiple unit types for sizing elements. Absolute units like px and pt have fixed values, while relative units like rem, em, and % scale with context. Understanding conversions is essential for responsive design.
Frequently Asked Questions
What is the base font size?
The default browser font size is 16px. Rem and em units are relative to this base — so 1rem = 16px by default.
What about vw and vh?
Viewport units (vw/vh) are calculated based on 1920×1080 viewport. 1vw = 1% of viewport width (19.2px at 1920px).