Find your ring size in seconds — type any measurement to convert instantly across all sizing systems.
Ring Size Converter
US Size
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UK Size
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EU Size
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Diameter
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Complete Ring Size Chart
All standard sizes from US 3 to US 13. Women's standard: US 7. Men's standard: US 10.
US / Canada
UK / Australia
EU / FR / IT
Japan
Diameter (mm)
Circumference (mm)
3
F
44
4
14.1
44.2
3.5
G
45
5
14.5
45.5
4
H
46
7
14.9
46.8
4.5
I
47
8
15.3
48.0
5
J
49
9
15.7
49.3
5.5
K
50
10
16.1
50.6
6
L
51
12
16.5
51.9
6.5
M
52
13
16.9
53.1
7 ★ Women's avg
N
54
14
17.3
54.4
7.5
O
55
15
17.7
55.7
8
P
57
16
18.1
57.0
8.5
Q
58
17
18.5
58.3
9
R
59
18
18.9
59.5
9.5
S
61
19
19.4
61.0
10 ★ Men's avg
T
62
20
19.8
62.2
10.5
U
63
21
20.2
63.5
11
V
65
22
20.6
64.7
11.5
W
66
23
21.0
66.0
12
X
67
24
21.4
67.3
12.5
Z
68
25
21.8
68.5
13
Z+1
70
27
22.2
69.7
Method 1: Measure with String or Paper
Cut a thin strip of paper or string about 6 inches long.
Wrap it snugly around the finger you want to size — not so tight it cuts off circulation.
Mark where the end meets the strip with a pen.
Lay flat and measure the length in mm — this is your circumference.
Divide by 3.14 to get your diameter in mm, then look up in the chart above.
Measure at the end of the day when fingers are largest. Cold shrinks fingers by up to half a size — avoid measuring first thing in the morning.
Method 2: Measure an Existing Ring
Choose a ring that fits the correct finger perfectly.
Place it flat on a ruler and measure the inside diameter in mm — measure across the center, not the edge.
Enter that number into the converter above, or look it up in the diameter column of the chart.
For wide bands (5mm+), size up by half a size — wide bands fit tighter than thin bands at the same nominal size.
Print this chart for in-store reference or as a gift shopping guide.
Frequently Asked Questions
What is the most common ring size for women?
The average women's ring size in the US is 7 (17.3mm diameter / 54.4mm circumference). Sizes 6 to 8 cover the majority of women's ring purchases. The most common engagement ring size bought as a surprise is 6.5.
What is the most common ring size for men?
The average men's ring size is 10 (19.8mm diameter / 62.2mm circumference). Men's sizes typically range from 8 to 14, with sizes 9 to 11 covering most purchases.
What if I'm between two ring sizes?
If you're between two sizes, size up for wide bands (4mm+) and size down for thin bands (under 3mm). Wide bands sit higher on the finger and feel tighter. If you tend to have swollen fingers in summer or after exercise, size up.
How do I convert EU ring size to US?
EU ring sizes are based on the inner circumference in mm. To convert: find your EU size in the chart above and read the corresponding US size. For example, EU 54 = US 7, EU 52 = US 6.5, EU 57 = US 8.
Can I resize a ring if it doesn't fit?
Yes — most metal rings can be resized up or down by 1 to 2 sizes by a jeweler. Sterling silver and gold rings resize easily. Rings with stones all the way around (eternity bands) are harder to resize. Tungsten and titanium cannot be resized at all.
Do fingers change size over time?
Yes. Fingers can change size with age, weight change, pregnancy, and temperature. A ring bought at 25 may not fit the same way at 35. Fingers are also slightly larger on your dominant hand. Always measure the specific finger you intend to wear the ring on.
