How do I measure my ring size at home?

Wrap a thin strip of paper or string around your finger at the knuckle (widest point). Mark where it overlaps, then measure the length in millimeters. This is your finger circumference. Divide by 3.14 to get diameter. Compare these measurements to a ring size chart for your country's sizing system.

What's the difference between US and UK ring sizes?

US ring sizes use a numerical scale (e.g., 6, 7, 8) based on diameter in inches, with each full size being approximately 0.032 inches larger. UK sizes use letters (e.g., L, M, N) with half sizes in between. A US size 6 equals approximately UK size L, and each UK letter represents about half a US size.

How do European ring sizes work?

European ring sizes represent the inner circumference of the ring in millimeters. For example, a size 52 ring has an inner circumference of 52mm. This makes European sizing straightforward if you measure your finger circumference. Common sizes range from 45-65, with size 52 being approximately average.

Should I size up for wide bands?

Yes, wider bands (over 8mm) should typically be sized up by 0.25-0.5 sizes because they fit more snugly. Wide bands cover more finger surface area and can feel tighter than thin bands in the same size. When in doubt, jewelers recommend going slightly larger for comfort, especially in warmer weather.

When is the best time to measure ring size?

Measure your ring size at the end of the day when fingers are warmest and slightly swollen. Avoid measuring when very cold, after exercise, or first thing in the morning, as fingers change size throughout the day and in different temperatures. Take multiple measurements for accuracy.

Everyday

Ring Size Calculator

Find your ring size by measuring finger diameter or circumference.

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Reference Chart

US Size	UK Size	Diameter (mm)	Circumference (mm)
3	F	14.1	44.2
3.5	G	14.5	45.5
4	H	14.9	46.8
4.5	I	15.3	48
5	J 1/2	15.7	49.3
5.5	K 1/2	16.1	50.6
6	L 1/2	16.5	51.9
6.5	M 1/2	16.9	53.1
7	N 1/2	17.3	54.4
7.5	O 1/2	17.7	55.7
8	P 1/2	18.1	57
8.5	Q 1/2	18.5	58.3
9	R 1/2	19	59.5
9.5	S 1/2	19.4	60.8
10	T 1/2	19.8	62.1
10.5	U 1/2	20.2	63.4
11	V 1/2	20.6	64.6
11.5	W 1/2	21	65.9
12	Y	21.4	67.2
12.5	Z	21.8	68.5
13	Z+1	22.2	69.7