Size guide

Find your ring size

Every Shell Diamonds ring is made to order in your exact size, at no extra cost. Sizes follow the Spanish scale (7–24); US and UK equivalents are approximate — we craft to the millimetre.

Measure your size

Two simple ways to find it. Measure at the end of the day, when your fingers are at their largest — and if you are between two sizes, choose the larger one.

With a ring that fits

Take a ring that fits the right finger well and measure its inner diameter in millimetres, edge to edge. Match it to the diameter column in the chart below — or place the ring over the printed circles.

With a strip of paper

Wrap a thin strip of paper or string around the base of your finger, mark where it overlaps and measure the length in millimetres. That is your circumference — match it to the chart below.

Size chart

Spanish size = inner circumference in millimetres minus 40 (ISO 8653). US and UK sizes are the closest equivalents.

Ring size conversion chart: Spanish size, inner circumference and diameter in millimetres, with approximate US and UK equivalents
Size (ES)	Circumference	Diameter	US	UK
7	47 mm	15.0 mm	4	H½
8	48 mm	15.3 mm	4½	I½
9	49 mm	15.6 mm	5	J
10	50 mm	15.9 mm	5¼	K
11	51 mm	16.2 mm	5¾	L
12	52 mm	16.5 mm	6	M
13	53 mm	16.9 mm	6½	N
14	54 mm	17.2 mm	7	O
15	55 mm	17.5 mm	7¼	P
16	56 mm	17.8 mm	7½	P½
17	57 mm	18.1 mm	8	Q
18	58 mm	18.5 mm	8½	R
19	59 mm	18.8 mm	9	S
20	60 mm	19.1 mm	9¼	S½
21	61 mm	19.4 mm	9¾	T½
22	62 mm	19.7 mm	10	U
23	63 mm	20.1 mm	10½	V
24	64 mm	20.4 mm	10¾	W

US and UK equivalents are indicative. Production always follows the millimetre measurement of the Spanish size you select.

Check with a real-size template

Print this page at 100% scale (no “fit to page”) and place a ring that fits over the circles below. Your size is the circle that matches the inner edge of the ring.

715.0 mm

815.3 mm

915.6 mm

1015.9 mm

1116.2 mm

1216.5 mm

1316.9 mm

1417.2 mm

1517.5 mm

1617.8 mm

1718.1 mm

1818.5 mm

1918.8 mm

2019.1 mm

2119.4 mm

2219.7 mm

2320.1 mm

2420.4 mm

Still unsure?

Message us and we will help you find the right size. And remember: all jewellery details and materials can be customised to your preferences — metal, carat and finish included.

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