Pleaserem unit
Safe to usecssThe css rem unit is calculated relative to font size, but based on the root element (usually <html>) instead of the element's parent.
- Verdict
- Safe to use
- Category
- CSS features
- Browser support
- Can I Use
- Works in
- IE9+
Should you use rem unit in 2026?
For a detailed comparison of em, px, and rem, see this post by Johnathan Snook.
Internet Explorer 10 and 9 have quirks. For more details see caniuse.