The Guide

Ring Size Guide

Find your fit, measure at home, or let us send you a free ring sizer.

Every SEMRĀ ring is made to order in standard U.S. sizes, in the exact size you choose. If you already know your size in another system, find it in the chart below and read across the row. Not sure yet? We'll mail you a free ring sizer.

ComplimentaryFree ring sizer, mailed to your doorRequest yours →

International Ring Size Chart

U.S. and Canadian sizes with their U.K. & Australian, European and Japanese equivalents, plus inside diameter and circumference (Diam., Circ.).

US	UK & AU	EU ISO	JP	Diam. mm	Circ. mm	Diam. in	Circ. in
3	F	44	4	14.1	44.2	0.554	1.74
3.5	G	45.5	5	14.5	45.5	0.570	1.79
4	H	47	7	14.9	46.8	0.586	1.84
4.5	I	48	8	15.3	48.0	0.602	1.89
5	J½	49.5	9	15.7	49.3	0.618	1.94
5.5	K½	50.5	10	16.1	50.6	0.634	1.99
6	L½	52	12	16.5	51.9	0.650	2.04
6.5	M½	53	13	16.9	53.1	0.666	2.09
7	N½	54.5	14	17.3	54.4	0.682	2.14
7.5	O½	55.5	15	17.7	55.7	0.698	2.19
8	P½	57	16	18.1	57.0	0.714	2.24
8.5	Q½	58	17	18.5	58.2	0.730	2.29
9	R½	59.5	18	18.9	59.5	0.746	2.34
9.5	S½	61	19	19.4	60.8	0.762	2.39
10	T½	62	20	19.8	62.1	0.778	2.44
10.5	U½	63.5	22	20.2	63.3	0.794	2.49
11	V½	64.5	23	20.6	64.6	0.810	2.54
11.5	W½	66	24	21.0	65.9	0.826	2.59
12	Y	67	25	21.4	67.2	0.842	2.64
12.5	Z	68.5	26	21.8	68.5	0.858	2.70
13	Z+1	69.5	27	22.2	69.7	0.874	2.75

Conversions are rounded to the nearest standard size, and scales vary slightly between makers. For a ring you plan to wear every day, measure with a proper ring sizer.

Most common sizes

Women

US 6 – 7

U.S. 6½ is the size we see most often.

Men

US 9 – 10

U.S. 10 is the most frequent.

Averages are only a starting point. Hands vary widely, so please measure.

How to measure at home

From a ring that fits

Choose a ring that fits the intended finger comfortably.
Measure the inside diameter straight across the middle, in millimeters.
Find that measurement in the chart. A ring measuring 16.5 mm inside is a U.S. 6.

From your finger

Wrap a thin strip of paper or string snugly around the base of the finger.
Mark where it overlaps and measure the length in millimeters.
That is your circumference. Find it in the chart: 51.9 mm is a U.S. 6.

Check the knuckle: the ring has to pass over it. If your knuckle is noticeably wider than the base of your finger, measure both and choose a size between them.

Paper and printed rulers are rarely precise enough. One millimeter is nearly half a size. For an engagement ring or a band you'll wear every day, use a proper sizer. We'll mail you one, free.

Get a free ring sizer

Getting the fit right

Band width. Wide bands (6 mm and up) fit more snugly. Consider going up a quarter to a half size.
Time of day. Fingers are smallest in the morning and largest in the evening. Measure at the end of the day.
Temperature. Cold hands measure small, warm hands large. Measure at room temperature.
Which hand. Your dominant hand is usually slightly larger.
Comfort fit. A rounded inner edge slides on more easily and can feel up to a quarter size looser.
Between sizes? Choose the larger one. A ring that is slightly loose is more comfortable than one that is tight.

Resizing at SEMRĀ

Each SEMRĀ ring includes one complimentary resize within 30 days of delivery, where the design allows. Shipping is at your expense. Resizing by more than one size may require an additional charge.

Some designs, such as eternity bands and pieces with stones set all around, cannot be resized. If you're unsure, ask us before you order. A ring that has been resized is no longer eligible for return. See Returns & Exchanges for details.

Ring size questions

What is the most common ring size for women?

U.S. 6 to 7, with 6½ the most common. Hands vary, so it is always worth measuring.

What is the most common ring size for men?

U.S. 9 to 10, with 10 the most common.

How do I convert a U.K. ring size to U.S.?

Find the U.K. letter in the chart and read across to the U.S. column. For example, U.K. M½ is a U.S. 6½.

How do I find my ring size in millimeters?

Measure the inside diameter of a ring that fits, or the circumference of your finger, and match it in the chart. 16.5 mm diameter or 51.9 mm circumference is a U.S. 6.

Does band width change the size I need?

Yes. Wider bands sit more snugly, so for bands of 6 mm or more consider going up a quarter to a half size.

What if I'm between two sizes?

Choose the larger size, especially for wider bands or if your knuckle is larger than the base of your finger.

Can my SEMRĀ ring be resized after purchase?

Most designs can. Each ring includes one complimentary resize within 30 days of delivery, where the design allows. Eternity and all-around set bands cannot be resized.

How does the free ring sizer work?

Fill in the form on this page with a U.S. address. We mail you a reusable plastic sizer, free, and it is yours to keep.