Ring Sizing
How To Measure Ring Sizes
- Measure the finger size at the end of the day when the finger is largest (like sizing shoes).
- Don’t measure the finger size when the hands are cold – let them warm up to room temperature
- At Worth & Douglas we measure sizes to the leading edge.
- If the finished ring will be wider than the ring gauges, you may require a slightly larger size. A narrower ring may require a slightly smaller size.
- Start with a size that slides easily onto the finger, and then progressively try smaller sizes until you find one which will not go on. The correct size will be about a half to one size larger.
- If you don’t have ring gauges, you can wrap a piece of string or a strip of paper around the finger. Mark the point where the two ends meet and measure this length to get the circumference of the finger.
The following table will convert the circumference to various ring size systems:
Ring Size Conversion Chart
| Comparison of Ring Sizes |
Circum |
Diameter |
| USA |
UK |
Japan |
Germany |
France |
Swiss |
mm |
mm |
| Ladies Sizes |
| 2.0 |
D |
2 |
13.25 |
41.25 |
1.50 |
41.5 |
13.2 |
| 2.5 |
E |
3 |
13.75 |
42.75 |
2.75 |
42.7 |
13.6 |
| 3.0 |
F |
4 |
14.00 |
44.00 |
4.00 |
44.0 |
14 |
| 3.5 |
G |
5 |
14.50 |
15.25 |
5.25 |
45.2 |
14.4 |
| 4.0 |
H |
7 |
15.00 |
16.50 |
7.75 |
46.5 |
14.8 |
| 4.5 |
I |
8 |
15.25 |
48.00 |
8.75 |
47.8 |
15.2 |
| 5.0 |
J |
9 |
15.75 |
50.00 |
9.00 |
49.0 |
15.6 |
| 5.5 |
K |
10 |
16.00 |
51.75 |
11.75 |
50.3 |
16 |
| 6.0 |
L |
12 |
16.50 |
52.75 |
12.75 |
51.5 |
16.4 |
| 6.5 |
M |
13 |
17.00 |
54.00 |
14.00 |
52.8 |
16.8 |
| 7.0 |
N |
14 |
17.25 |
55.25 |
16.25 |
54.0 |
17.2 |
| 7.5 |
O |
15 |
17.75 |
56.50 |
16.50 |
55.3 |
17.6 |
| 8.0 |
P |
16 |
18.00 |
57.75 |
17.75 |
56.6 |
18 |
| 8.5 |
Q |
17 |
18.50 |
58.00 |
19.00 |
57.8 |
18.4 |
| 9.0 |
R |
18 |
19.00 |
60.00 |
20.25 |
59.1 |
18.8 |
| Gents Sizes |
| 9.5 |
S |
19 |
19.50 |
61.25 |
21.50 |
60.3 |
19.2 |
| 10.0 |
T |
20 |
20.00 |
62.00 |
22.50 |
61.6 |
19.6 |
| 10.5 |
U |
22 |
20.25 |
63.25 |
23.00 |
62.8 |
20 |
| 11.0 |
V |
23 |
20.75 |
65.00 |
24.00 |
64.1 |
20.4 |
| 11.5 |
W |
24 |
21.00 |
66.0 |
26.00 |
65.3 |
20.8 |
| 12.0 |
X |
25 |
21.25 |
67.50 |
27.50 |
66.6 |
21.2 |
| 12.5 |
Y |
26 |
21.75 |
68.75 |
28.75 |
67.8 |
21.6 |
| 13.0 |
Z |
27 |
22.00 |
69.00 |
30.00 |
69.1 |
22 |
| 13.5 |
Z + 1 |
- |
- |
- |
- |
- |
- |
| 14.0 |
Z + 2 |
- |
- |
- |
- |
- |
- |
| 14.5 |
Z + 3 |
- |
- |
- |
- |
- |
- |
Formulae
AU, NZ and UK size = (circumference in mm – 36.667) x .8085
1 = A, 2 = B, etc
USA size = (circumference in mm – 36.107) x .3862
Singapore & Europe size = circumference in mm
Japan size = (circumference in mm – 39.7946) x .9549
How do I correctly measure a customer’s finger size?
When measuring a customer’s finger size you must be aware of the width of the ring sizer you are using.
When a customer is purchasing a 3mm wide ring and you are using a 3mm wide ring sizer, the size remains that which was measured.
If you are using a 3mm wide ring sizer but the ring purchased is 5mm wide, then you must add half a size for every 2mm variance in width.
| Eg. |
3mm wide ring sizer, customer measures size R
Ring being ordered is 3mm wide
Order product in size R |
| Eg. |
3mm wide ring sizer, customer measures size R
Ring being ordered is 5mm wide
Order product in size R ½ |
| Eg. |
3mm wide ring sizer, customer measures size R
Ring being ordered is 7mm wide
Order product in size S |
Remember our rings are sized to the leading edge and a wider "Comfort Curve™" ring appears slightly larger because the centre of the ring touches the ring stick first.