Ring Size Conversion Chart

Please have a look at our article on Determining Your Ring Size if you don’t know your size.

Inside diameter
(inches)
Inside diameter
(mm)
Inside circ.
(inches)
Inside circ.
(mm)
Numerical sizes
(US, Canada)
Alphabetical sizes
(Australia, UK, etc)
0.458″ 11.6 mm 1.438″ 36.5 mm 0
0.466″ 11.8 mm 1.463″ 37.2 mm 1/4
0.474″ 12 mm 1.488″ 37.8 mm 1/2 A
0.482″ 12.2 mm 1.513″ 38.4 mm 3/4 A 1/2
0.49″ 12.4 mm 1.539″ 39.1 mm 1 B
0.498″ 12.6 mm 1.564″ 39.7 mm 1 1/4 B 1/2
0.506″ 12.9 mm 1.589″ 40.4 mm 1 1/2 C
0.514″ 13.1 mm 1.614″ 41 mm 1 3/4 C 1/2
0.522″ 13.3 mm 1.639″ 41.6 mm 2 D
0.53″ 13.5 mm 1.664″ 42.3 mm 2 1/4 D 1/2
0.538″ 13.7 mm 1.689″ 42.9 mm 2 1/2 E
0.546″ 13.9 mm 1.714″ 43.5 mm 2 3/4 E 1/2
0.554″ 14.1 mm 1.74″ 44.2 mm 3 F
0.562″ 14.3 mm 1.765″ 44.8 mm 3 1/4 F 1/2
0.57″ 14.5 mm 1.79″ 45.5 mm 3 1/2 G
0.578″ 14.7 mm 1.815″ 46.1 mm 3 3/4 G 1/2
0.586″ 14.9 mm 1.84″ 46.7 mm 4 H
0.594″ 15.1 mm 1.865″ 47.4 mm 4 1/4 H 1/2
0.602″ 15.3 mm 1.89″ 48 mm 4 1/2 I
0.61″ 15.5 mm 1.915″ 48.7 mm 4 3/4 J
0.618″ 15.7 mm 1.941″ 49.3 mm 5 J 1/2
0.626″ 15.9 mm 1.966″ 49.9 mm 5 1/4 K
0.634″ 16.1 mm 1.991″ 50.6 mm 5 1/2 K 1/2
0.642″ 16.3 mm 2.016″ 51.2 mm 5 3/4 L
0.65″ 16.5 mm 2.041″ 51.8 mm 6 L 1/2
0.658″ 16.7 mm 2.066″ 52.5 mm 6 1/4 M
0.666″ 16.9 mm 2.091″ 53.1 mm 6 1/2 M 1/2
0.674″ 17.1 mm 2.116″ 53.8 mm 6 3/4 N
0.682″ 17.3 mm 2.141″ 54.4 mm 7 N 1/2
0.69″ 17.5 mm 2.167″ 55 mm 7 1/4 O
0.698″ 17.7 mm 2.192″ 55.7 mm 7 1/2 O 1/2
0.706″ 17.9 mm 2.217″ 56.3 mm 7 3/4 P
0.714″ 18.1 mm 2.242″ 56.9 mm 8 P 1/2
0.722″ 18.3 mm 2.267″ 57.6 mm 8 1/4 Q
0.73″ 18.5 mm 2.292″ 58.2 mm 8 1/2 Q 1/2
0.738″ 18.7 mm 2.317″ 58.9 mm 8 3/4 R
0.746″ 18.9 mm 2.342″ 59.5 mm 9 R 1/2
0.754″ 19.2 mm 2.368″ 60.1 mm 9 1/4 S
0.762″ 19.4 mm 2.393″ 60.8 mm 9 1/2 S 1/2
0.77″ 19.6 mm 2.418″ 61.4 mm 9 3/4 T
0.778″ 19.8 mm 2.443″ 62.1 mm 10 T 1/2
0.786″ 20 mm 2.468″ 62.7 mm 10 1/4 U
0.794″ 20.2 mm 2.493″ 63.3 mm 10 1/2 U 1/2
0.802″ 20.4 mm 2.518″ 64 mm 10 3/4 V
0.81″ 20.6 mm 2.543″ 64.6 mm 11 V 1/2
0.818″ 20.8 mm 2.569″ 65.2 mm 11 1/4 W
0.826″ 21 mm 2.594″ 65.9 mm 11 1/2 W 1/2
0.834″ 21.2 mm 2.619″ 66.5 mm 11 3/4 X
0.842″ 21.4 mm 2.644″ 67.2 mm 12 X 1/2
0.85″ 21.6 mm 2.669″ 67.8 mm 12 1/4 Y
0.858″ 21.8 mm 2.694″ 68.4 mm 12 1/2 Z
0.866″ 22 mm 2.719″ 69.1 mm 12 3/4 Z 1/2
0.874″ 22.2 mm 2.744″ 69.7 mm 13
0.882″ 22.4 mm 2.769″ 70.3 mm 13 1/4 Z1
0.89″ 22.6 mm 2.795″ 71 mm 13 1/2
0.898″ 22.8 mm 2.82″ 71.6 mm 13 3/4 Z2
0.906″ 23 mm 2.845″ 72.3 mm 14 Z3
0.914″ 23.2 mm 2.87″ 72.9 mm 14 1/4
0.922″ 23.4 mm 2.895″ 73.5 mm 14 1/2 Z4
0.93″ 23.6 mm 2.92″ 74.2 mm 14 3/4
0.938″ 23.8 mm 2.945″ 74.8 mm 15
0.946″ 24 mm 2.97″ 75.4 mm 15 1/4
0.954″ 24.2 mm 2.996″ 76.1 mm 15 1/2
0.962″ 24.4 mm 3.021″ 76.7 mm 15 3/4
0.97″ 24.6 mm 3.046″ 77.4 mm 16