How to Calculate Ring Size
What is Ring Size?
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.
Formula
Step-by-Step Guide
- 1Measure circumference with flexible tape in mm
- 2EU size = circumference (mm) − 40
- 3UK sizes use letters; US uses numbers
- 4Sizes vary by country — use conversion chart for international orders
Worked Examples
Frequently Asked Questions
What is Ring Size?
Ring sizing is based on finger circumference. US uses a numerical scale; EU sizes equal circumference in mm minus 40; UK uses letters
How accurate is the Ring Size calculator?
The calculator uses the standard published formula for ring size. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.
What units does the Ring Size calculator use?
This calculator works with inches. You can enter values in the units shown — the calculator handles all conversions internally.
What formula does the Ring Size calculator use?
The core formula is: EU size = circumference (mm) − 40. Each step in the calculation is shown so you can verify the result manually.
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