Ring Sizing Tips and Tools

It would be nice if a universal approach to ring sizing existed, but it doesn't. Many countries differ in the sizing systems they use and even within the same system, there seems to be some variance in the measurements on a company by company basis.

There are a number of factors to consider when purchasing a ring, whether it happens to be modern or antique. How do I choose my size? If the ring is sized, will the finished result look good? I would like to purchase an English antique ring that is a size "J," how do I convert that to a size that I am familiar with? We hope the following information will help you better understand some of the factors you may want to consider when choosing and sizing a ring.

Sizing Systems

The US and Canadian system of sizing rings, increases in increments of ¼, ( e.g. 6, 6 1/4, 6 1/2, etc.) using a numerical scale. The UK system uses a letter scheme with ½ size increments (e.g. K, K ½, L, etc.).

Ring and Finger Sizing Tools

A ring mandrel is the name of the a stick (smaller at the top and larger at the base) that is used to measure the size of a ring.

A set of sizing rings is used to determine the ring size of a finger. Start with a size you think is close and keep trying on the next ring in the series (progressively smaller or larger) until you find the one that fits.

Sizing Tips

Ideally, you want a ring that will fit snugly, but that is not uncomfortable. If it is too loose, there is a possibility of it sliding off. It is not unusual for the left hand to differ from the right hand, so measure the hand/finger on which you want to wear the ring. When the ring band is wider, it is usually wise to pick a size that is a little larger than that of a narrower band. Consider the time of day and temperature. Your fingers tend to be a little larger at the end of the day and a little smaller when the temperature is cool (try to warm your hands up to room temperature). It is not as complicated as it sounds and keep in mind that the difference between a size US 5 1/2 and a US 6 is only a little more than a 1% difference in the total circumference.

Most rings can be sized up or down, and many can be sized without any tell tale signs, but this is not the case for all rings and it can depend upon the skill of your jeweler. Note that in our descriptions, the result the we believe is achievable is with a skilled jeweler.

Regardless of who does the work, you should consider the following: pattern, shape, setting, metal, and up or down. Here are some of the issues you should consider before purchasing a ring with the intention of having it sized and the questions you should ask your jeweler before dropping it off to have the work done. Always ask about what the finished product will look like and how much it will cost prior to leaving the ring.

Pattern: Does it have a pattern or shape that will be interrupted if sized? Ask your jeweler what impact the pattern will have on sizing and what the outside of the band will look like when the work is completed.

Eternity band without a sizing bar: Does the ring have stones all the way around? How much work will it require? If it is sized up, can matching stones be found? Unless there is a sizing bar, it is usually best not to try to size and eternity ring as it is likely to involve a lot of work and expense.

Metal color: Is it an antique ring whose metal color could be challenging for your jeweler to match? This is more of an issue in sizing up. Either way ask whether or not there will be a color difference or a line of any sort when completed.

Cost of materials: When a ring is sized up, it requires the purchase of additional metal (although most likely a small amount) which can cost more than sizing down. It will also depend upon whether it is a straight forward job and how much you care about what the back of your ring looks like.

A quick fix: You can always have a ring guard added if the ring is on the big side and you don't want to have it sized.

Lastly, take care when sizing a ring that has hallmarks/stamps, if that is something you want to preserve. You may or may not. You may love the ring and just want it to fit, making this factor a non-issue.

Conversion Chart

When reviewing the chart below keep in mind many published charts seem to use slightly different methodologies. The left two columns represent the inside circumference (in millimeters and inches) of the ring sizes in the columns to the right.

 

Inside CIRC MM

Inside CIRC Inches

US Size

UK Size

EU Size

39.1 1.54 1 B  
39.7 1.56 1  1/4 B  1/2  
40.4 1.59 1  1/2 C  
41.0 1.61 1  3/4 C  1/2  
41.7 1.64 2 D  
42.3 1.67 2  1/4 D  1/2  
42.9 1.69 2  1/2 E  
43.6 1.72 2  3/4 E  1/2  
44.2 1.74 3 F  
44.8 1.76 3  1/4 F  1/2  
45.5 1.79 3  1/2 G  
46.1 1.81 3  3/4 G  1/2  
46.8 1.84 4 H  
47.4 1.87 4  1/4 H  1/2  
48.0 1.89 4  1/2 I  
48.7 1.92 4  3/4 J 10
49.3 1.94 5 J  1/2 10/11
50.0 1.97 5  1/4 K 11
50.6 1.99 5  1/2 K  1/2 12
51.2 2.02 5  3/4 L 12/13
51.9 2.04 6 L  1/2 13
52.5 2.07 6  1/4 M 14
53.1 2.09 6  1/2 M  1/2 14/15
53.8 2.12 6  3/4 N 15
54.4 2.14 7 N  1/2 15/16
55.1 2.17 7  1/4 O 16
55.7 2.19 7  1/2 O  1/2 17
56.3 2.22 7  3/4 P 17/18
57.0 2.24 8 P  1/2 18
57.6 2.27 8  1/4 Q 18/19
58.3 2.30 8  1/2 Q  1/2  
58.9 2.32 8  3/4 R  
59.5 2.34 9 R  1/2  
60.2 2.37 9  1/4 S  
60.8 2.39 9  1/2 S  1/2  
61.4 2.42 9  3/4 T  
62.1 2.44 10 T  1/2  
62.7 2.47 10  1/4 U  
63.4 2.50 10  1/2 U  1/2  
64.0 2.52 10  3/4 V  
64.6 2.54 11 V  1/2