How to Properly Obtain the Ring Size for an Engagement Ring

How to Properly Obtain the Ring Size for an Engagement Ring


Obtaining the correct finger size and confirming the ring is actually sized to the correct ring size would appear to be a very simple task. However considering the finger size and all of the conditions affecting the variables to consider such as; water retention, arthritis, previously broken finger joint, weight loss or gain, current body temperature, room temperature, and hand moisture level can affect obtaining the proper finger size for a ring. These are just a few of the considerations for obtaining a proper finger size as expressed by a colleague of mine who has over 40 years of retail diamond jewelry sales experience.Before obtaining the finger size, the person determining the correct finger size should determine if their client’s hands are warm or cool to the touch. When the client is asked this question they always respond to yes I’m usually cold or warm. This relates to blood flow in the hand and everyone knows when they go outside in the winter snow, their body becomes chilly and their rings tend to slip around on the finger as their body fluids contract. Conversely the warm summer temperatures expand the body fluids which tend to make rings fit tight. Another example is the effect a woman’s monthly cycle has on water retention making rings fit tighter or looser depending on the time of the month. Properly fitting a ring to an arthritic finger is problematic as the knuckles are always quite a bit larger than the ring size which makes fitting a ring properly a challenge.

The millimeter width of the ring shank is an important consideration.

Rule of Thumb: The wider the shank the larger the ring size. This means if your ring size is 7 and the millimeter width size of the shank is 4 mm or larger you must add one half size to the measured finger size to compensate for the size of the ring.

When obtaining a finger size for a ring which has a heavy top meaning larger diamond or color stone the ring needs to be fitted as tight as possible at the knuckle which allows best fit in the wearing position. In the event the knuckle is large and actual finger size is relatively small a special condition requiring a custom-made stainless steel insert ring soldered to the inside base of the ring’s shank. The reason we stainless steel is because of its tensile strength and tension memory. I used this technique on many clients’ rings always receiving excellent results.

In the case of the arthritic finger a special patented finger fit shank can be installed which works similarly to a belt with a buckle clasp. It opens three sizes to pass over the knuckle, then closes to fit the smaller part of the finger where the ring is worn preventing the ring from flopping and twisting around on your finger.

Get a printable worksheet to determine your ring size!

Click here to download & print

International Ring Size Tables

Size (inches) Size (mm) Diameter (mm) U.S.A. size Japanese size British size German size Swiss size
1 14/16 48 15.27 4 1/2 8 I – 1/2 15 1/4
1 15/16 49 15.70 5 9 J 1/2 15 3/4
2 51 16.10 5 1/2 11 L 16 11 3/4
2 1/16 52 16.51 6 12 M 16 1/2 12 3/4
2 2/16 53 16.92 6 1/2 13 N 17 14
2 3/16 55 17.35 7 14 O 17 1/4 15 1/4
2 4/16 56 17.75 7 1/2 15 P 17 3/4 16 1/2
2 5/16 57 18.19 8 16 Q 18 17 3/4
2 6/16 58 18.53 8 1/2 17 Q 1/2 18 1/2
2 7/16 59 18.89 9 18 R 1/2 19
2 8/16 61 19.41 9 1/2 19 S 1/2 19 1/2
2 9/16 62 19.84 10 20 T 1/2 20
2 10/16 63 20.20 10 1/2 22 U 1/2 20 1/4
2 11/16 65 20.68 11 23 V 1/2 20 3/4
2 12/16 66 21.08 11 1/2 24 W 1/2 21
2 13/16 68 21.49 12 25 Y 21 1/4 27 1/2
2 14/16 69 21.89 12 1/2 26 Z 21 3/4 28 3/4
2 15/16 70 22.33 13 27 22
Size
(inches)
Size
(mm)
Diameter
(mm)
U.S.A.
size
Australian
size
Italian
size
French
size
1 14/16 48 15.27 4 1/2 I 1/2 8
1 15/16 49 15.70 5 J 1/2 9.5
2 51 16.10 5 1/2 L 10.5 51 3/4
2 1/16 52 16.51 6 M 11.5 52 3/4
2 2/16 53 16.92 6 1/2 N 13 54
2 3/16 55 17.35 7 O 14.5 55 1/4
2 4/16 56 17.75 7 1/2 P 16 56 1/2
2 5/16 57 18.19 8 Q 17 57 3/4
2 6/16 58 18.53 8 1/2 Q 1/2 18.5 58
2 7/16 59 18.89 9 R 1/2 19.5 59 1/4
2 8/16 61 19.41 9 1/2 S 1/2 21 60 1/2
2 9/16 62 19.84 10 T 1/2 22 61 3/4
2 10/16 63 20.20 10 1/2 U 1/2 23.5 62 3/4
2 11/16 65 20.68 11 V 1/2 25 64 1/4
2 12/16 66 21.08 11 1/2 W 1/2 26.5 66
2 13/16 68 21.49 12 Y 27.5 67 1/2
2 14/16 69 21.89 12 1/2 Z 28.5 68 3/4
2 15/16 70 22.33 13 30
Frank Fisher

Author: Frank Fisher

Frank Fisher (Sasha Evdakov) started learning about diamonds at a young age through his cultural background and family influence. He spent years being mentored by the best diamond dealers and has been studying diamonds and the diamond market since 1998.
  • http://www.facebook.com/people/Jake-Johnson/100005282052200 Jake Johnson

    This is some great information about large size rings. This is always good to know.