Ring Size Calculator
Circumference
Unit
Ring sizing is based on finger circumference. US uses a numerical scale; EU sizes equal circumference in mm minus 40; UK uses letters. Measure at end of day when fingers are slightly larger.
References
🔒
100% Free
No sign-up ever
✓
Accurate
Verified formulas
⚡
Instant
Results as you type
📱
Mobile Ready
All devices