UK size · Inside diameter · Inside circumference
All measurements are in millimetres and are approximate.
A · 12.1 mm · 37.5 mm
B · 12.5 mm · 39.0 mm
C · 12.9 mm · 40.2 mm
D · 13.2 mm · 41.4 mm
E · 13.6 mm · 42.6 mm
F · 14.0 mm · 43.8 mm
G · 14.4 mm · 45.0 mm
H · 14.8 mm · 46.2 mm
I · 15.2 mm · 47.4 mm
J · 15.6 mm · 48.6 mm
K · 16.0 mm · 49.8 mm
L · 16.4 mm · 51.0 mm
M · 16.8 mm · 52.2 mm
N · 17.2 mm · 53.5 mm
O · 17.6 mm · 54.7 mm
P · 18.0 mm · 56.0 mm
Q · 18.4 mm · 57.3 mm
R · 18.8 mm · 58.6 mm
S · 19.2 mm · 59.9 mm
T · 19.5 mm · 61.1 mm
U · 19.9 mm · 62.4 mm
V · 20.3 mm · 63.7 mm
W · 20.7 mm · 64.9 mm
X · 21.1 mm · 66.1 mm
Y · 21.5 mm · 67.3 mm
Z · 21.9 mm · 68.5 mm
How to check your size
Measure straight across the inside centre of a ring that fits the same finger, excluding the metal. Compare this with the inside diameter above. For the most reliable fit, have your finger measured with a proper ring sizer.
Wide bands and stacks can feel tighter than a narrow ring. Half sizes fall between the letters shown. Check the size stated on each listing; handmade rings may vary slightly. For adjustable rings, contact me to check the comfortable adjustment range. If you are unsure, please get in touch before ordering.
Reference measurements: Cooksongold ring sizing chart.
