Ring Size Conversion

Ring size conversion table between American (US), UK, Australian, Canadian, Japanese and Chinese ring sizes including the diameters in inches and millimeters (mm).

To view all size conversion tables, please visit size conversions.

International Ring Size Table

US / CAN / MXUK / AUS / NZ / IRLChina / Japan / KoreaContinental EuropeDiameter (inch)Diameter (mm)
0--36.50.45811.63
¼--37.20.46611.84
½A-37.80.47412.04
¾-38.50.48212.24
1B139.10.4912.45
-39.70.49812.65
C-40.40.50612.85
-410.51413.06
2D241.70.52213.26
- 42.30.5313.46
E342.90.53813.67
-43.60.54613.87
3F444.20.55414.07
544.80.56214.27
G-45.50.5714.48
646.10.57814.68
4H746.80.58614.88
-47.40.59415.09
I8480.60215.29
J-48.70.6115.49
5949.30.61815.70
K-500.62615.90
10 50.60.63416.10
L-51.20.64216.31
61151.90.6516.51
M1252.50.65816.71
1353.10.66616.92
N-53.80.67417.12
71454.40.68217.32
O-55.10.6917.53
1555.70.69817.73
P-56.30.70617.93
816570.71418.14
Q-57.60.72218.34
1758.30.7318.54
R- 58.90.73818.75
91859.50.74618.95
S-60.20.75419.15
1960.80.76219.35
T-61.40.7719.56
102062.10.77819.76
10¼U2162.70.78619.96
10½2263.40.79420.17
10¾V-640.80220.37
112364.60.8120.57
11¼W-65.30.81820.78
11½2465.90.82620.98
11¾X-66.60.83421.18
1225 67.20.84221.39
12¼Y-67.80.8521.59
12½Z2668.50.85821.79
12¾-69.10.86622.00
13-2769.70.87422.20
13¼Z1-70.40.88222.40
13½--710.8922.61
13¾Z2-71.70.89822.81
14Z3-72.30.90623.01
14¼--72.90.91423.22
14½Z4-73.60.92223.42
14¾--74.20.9323.62
15--74.80.93823.83
15¼-- 75.50.94624.03
15½--76.10.95424.23
15¾--76.80.96224.43
16--77.40.9724.64

US, Canada and Mexico have the same ring sizes and use numerical values with quarter and half sizes for ring size measurement.

UK, Australia, New Zealand, Ireland and South Africa have the same ring sizes and use the letters of the alphabet with half sizes for ring size measurement.

The continental European countries Austria, France, Germany, Belgium, Norway, Sweden, Denmark, Finland, Iceland use the inner circumference of the ring measured in millimeters as ring measurement standard.

China, Japan, South Korea and South America have the same ring sizes and use numerical values with whole sizes.