Ring Size Conversion Guide

This ring size chart is based on our closest conversions. When in doubt, size 1/4 size up for a slightly looser fit and vice versa.

US/Canada Inside Diameter (mm) Inside Circumference (mm)
3 14.05mm 44.14mm
3 1/4 14.25mm 44.77mm
3 1/2 14.45mm 45.40mm
3 3/4 14.65mm 46.02mm
4 14.86mm 46.68mm
4 1/4 15.04mm 47.25mm
4 1/2 15.27mm 47.97mm
4 3/4 15.53mm 48.79mm
5 15.70mm 49.32mm
5 1/4 15.90mm 49.95mm
5 1/2 16.10mm 50.58mm
5 3/4 16.30mm 51.21mm
6 16.51mm 51.87mm
6 1/4 16.71mm 52.50mm
6 1/2 16.92mm 53.16mm
6 3/4 17.13mm 53.82mm
7 17.35mm 54.51mm
7 1/4 17.45mm 54.82mm
7 1/2 17.75mm 55.76mm
7 3/4 17.97mm 56.45mm
8 18.19mm 57.15mm
8 1/4 18.35mm 57.65mm
8 1/2 18.53mm 58.21mm
8 3/4 18.69mm 58.72mm
9 18.89mm 59.34mm
9 1/4 19.22mm 60.38mm
9 1/2 19.41mm 60.98mm
9 3/4 19.62mm 61.64mm
10 19.84mm 62.33mm
10 1/4 20.02mm 62.89mm
10 1/2 20.20mm 63.46mm
10 3/4 20.44mm 64.21mm
11 20.68mm 64.97mm
11 1/4 20.85mm 65.50mm
11 1/2 21.08mm 66.22mm
11 3/4 21.24mm 66.73mm
12 21.49mm 67.51mm
12 1/4 21.69mm 68.14mm
12 1/2 21.89mm 68.77mm
12 3/4 22.10mm 69.43mm
13 22.33mm 70.15mm

 

Choosing the right size can be tricky, there are some instances where you may have to size up or down. Learn more in our Size Guide Page.