Ring Size Chart
Jewelry fitting
Ring Size
Guide
Find your perfect fit before ordering a custom keepsake ring
A keepsake ring is made to be worn every day, as a permanent reminder of someone irreplaceable. Getting the size right matters — this guide gives you two simple ways to measure, plus an instant size calculator.
On this page
Instant calculator
Enter Your Ring Diameter
Measure the inner diameter of a ring that already fits the intended finger, then enter it below. Or use the slider to explore sizes.
Your US ring size
—
Before you measure
Measure at the Right Time
Fingers change size throughout the day and with temperature. Measure at the end of the day, when fingers are at their largest. Avoid measuring first thing in the morning or in very cold conditions — both can give you an inaccurate reading.
Account for Your Knuckle
If your knuckle is noticeably wider than the base of your finger, size for the knuckle — the ring needs to pass over it. A ring that fits the base but won't clear the knuckle is unusable.
Not Sure? Size Up
When a measurement falls right between two sizes, the larger size is almost always more comfortable for daily wear. A ring that's slightly loose is easier to resize than one that's too tight.
Reference table
US sizes & their
exact measurements
| US Size | Diameter (mm) | Circumference (mm) | Fits up to |
|---|---|---|---|
| 4 | 14.9 | 46.8 | 14.9 mm diameter |
| 5 | 15.7 | 49.3 | 15.7 mm diameter |
| 6 | 16.5 | 51.8 | 16.5 mm diameter |
| 7 | 17.3 | 54.4 | 17.3 mm diameter |
| 8 | 18.1 | 56.9 | 18.1 mm diameter |
| 9 | 18.9 | 59.5 | 18.9 mm diameter |
| 10 | 19.8 | 62.1 | 19.8 mm diameter |
Each row shows the maximum diameter for that size. Measurements between sizes → round up.
Two methods
How to find your measurement
Method A
Measure an existing ring
- Choose a ring that fits the intended finger well.
- Lay it flat on a ruler or use a caliper.
- Measure the inner diameter — the gap across the inside of the band — in millimeters.
- Enter that number in the calculator above.
Method B
Measure your finger
- Cut a thin strip of paper or use a piece of string.
- Wrap it snugly around the base of the finger.
- Mark where the paper meets itself, then measure the length with a ruler — this is your circumference in mm.
- Divide by 3.14159 to get your diameter, then use the calculator.
Tip
No ruler? Most standard printer paper is 210 mm wide. Fold it into a narrow strip and use the fold lines to estimate millimeter lengths. It won't replace a proper ruler but it's a useful starting point.
Ready to order?
Your size is
just the beginning
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