Getting your ring size right is essential when buying online. An ill-fitting ring can be uncomfortable or, worse, fall off. The good news is that measuring your ring size at home is straightforward with a few simple methods.
Method 1: The String Method
- Cut a thin strip of paper or a piece of string about 6 inches long
- Wrap it around the base of your finger (where the ring will sit)
- Mark where the paper or string overlaps
- Measure the length in millimeters using a ruler
- Compare to the size chart below
Important: Measure at the end of the day when your fingers are at their largest. Avoid measuring when your hands are cold, as fingers shrink in cold temperatures.
Method 2: Use an Existing Ring
If you already own a ring that fits well, measure its inner diameter in millimeters and compare it to the chart below. Place the ring on a ruler and measure from one inside edge to the other.
US Ring Size Chart
| US Size | Inner Diameter (mm) | Inner Circumference (mm) |
|---|---|---|
| 4 | 14.9 | 46.8 |
| 4.5 | 15.3 | 48.0 |
| 5 | 15.7 | 49.3 |
| 5.5 | 16.1 | 50.6 |
| 6 | 16.5 | 51.9 |
| 6.5 | 16.9 | 53.1 |
| 7 | 17.3 | 54.4 |
| 7.5 | 17.7 | 55.7 |
| 8 | 18.1 | 57.0 |
| 8.5 | 18.5 | 58.3 |
| 9 | 18.9 | 59.5 |
| 9.5 | 19.4 | 60.8 |
| 10 | 19.8 | 62.1 |
| 10.5 | 20.2 | 63.4 |
| 11 | 20.6 | 64.6 |
| 11.5 | 21.0 | 65.9 |
| 12 | 21.4 | 67.2 |
International Size Conversion
| US | UK | EU | Japan |
|---|---|---|---|
| 5 | J 1/2 | 49 | 9 |
| 6 | L 1/2 | 52 | 12 |
| 7 | N 1/2 | 54 | 14 |
| 8 | P 1/2 | 57 | 16 |
| 9 | R 1/2 | 59 | 19 |
| 10 | T 1/2 | 62 | 21 |
| 11 | V 1/2 | 65 | 23 |
| 12 | X 1/2 | 67 | 25 |
Tips for Accurate Sizing
- Measure multiple times: Take 3 measurements at different times of day and use the average
- Consider width: Wider bands (6mm+) typically need a half size larger than thin bands
- Account for knuckle size: If your knuckle is larger than your finger base, measure both and choose a size in between
- When in doubt, go up: It is easier to have a ring sized down than up
- Temperature matters: Fingers swell in heat and shrink in cold, so room temperature is ideal
Ordering Online? Many Amazon sellers include free ring sizers with orders, or you can buy a dedicated ring sizer set for under $5. It is the best investment before buying a ring online.
Common Ring Size by Finger
- Women's average ring finger: US size 6 to 6.5
- Men's average ring finger: US size 9 to 10
- Pinky rings: Typically 1.5 to 2 sizes smaller than ring finger
- Index/middle finger: Typically 0.5 to 1 size larger than ring finger