How to Know Your Ring Size
Finding the right ring size ensures your piece fits comfortably—secure enough not to slip off, but loose enough to slide over your knuckle. Here is a simple, step-by-step guide to measuring your finger accurately using items you already have at home.
What You Need
-
A piece of non-stretchy string, ribbon, or a narrow strip of paper
-
A ruler (with millimeter/cm markings)
-
A pen or marker
Three Simple Steps to Measure Your Finger
Step 1: Wrap and Position
Wrap the string snugly around the base of the finger you intend to wear the ring on.
Tip: Make sure to slide the loop up over your knuckle as well! Your knuckle is often slightly wider than the base of your finger, so the ring needs to be able to pass over it comfortably.
Step 2: Mark the Overlap
Where the end of the string to form a complete circle, use a pen to draw a clear mark across both layers.
(Visual Placeholder: An illustration showing a pen marking the exact point where the paper strip meets)
Step 3: Measure the Length
Lay the string or paper flat against a ruler. Measure the distance from the end to your mark in millimeters (mm). This measurement is your finger's inner circumference.
(Visual Placeholder: An illustration of a flattened strip of paper measured against a ruler in millimeters)
Helpful Tips for Best Accuracy
-
Measure at the end of the day: Fingers tend to be slightly smaller in the morning or when you are cold. Measuring in the evening when your hands are warm yields the most reliable size.
-
Measure multiple times: Do this 2 or 3 times to make sure your measurement is consistent.
-
When in doubt, size up: If your measurement falls between two sizes, it is usually best to choose the larger size for comfort.
Ring Size Comparison Chart (US vs. AU / UK)
Below is a reference guide matching your finger's circumference (in millimeters) to US and Australian/UK standard ring sizes.
Inside Circumference (mm) US / Canada Size Australia / UK Size
44.2 mm 3 F
46.8 mm 4 H
49.3 mm 5 J 1/2
51.9 mm 6 M
54.4 mm 7 O
57.0 mm 8 Q
59.5 mm 9 S
62.1 mm 10 U
64.6 mm 11 W
67.2 mm 12 Y
Below is HONGKONG size to US and AU
HK Size (Circumference) (Diameter) (US size ) AU/UK size
6 44.2 mm 14.1 mm US 3 F
7 45.5 mm 14.5 mm US 3.5 G
8 46.8 mm 14.9 mm US 4 H
9 48.0 mm 15.3 mm US 4.5 I
10 49.3 mm 15.7 mm US 5 J 1/2
11 50.6 mm 16.1 mm US 5.5 K 1/2
12 52.0 mm 16.5 mm US 6 L 1/2
13 53.1 mm 16.9 mm US 6.5 M
14 54.4 mm 17.3 mm US 7 N
15 55.7 mm 17.7 mm US 7.5 O
16 57.0 mm 18.1 mm US 8 P
17 58.3 mm 18.5 mm US 8.5 Q
18 59.5 mm 18.9 mm US 9 R
19 60.8 mm 19.4 mm US 9.5 S
20 62.1 mm 19.8 mm US 10 T 1/2
21 63.4 mm 20.2 mm US 10.5 U 1/2
22 64.7 mm 20.6 mm US 11 V 1/2
23 66.0 mm 21.0 mm US 11.5 W 1/2
24 67.2 mm 21.4 mm US 12 X
25 68.5 mm 21.8 mm US 12.5 Y