Class Ring Sizing Guide
Find your class ring size
Professional sizing is the best way to choose a comfortable fit before ordering your class ring.
Available sizes
Our ring-size reference includes sizes from 0.5 through 13, but available sizes vary by design. The Prism Class Ring description lists sizes 5 through 14. Always check the size options on the specific product before ordering. This chart is a measurement reference, not a promise that every size is available.
US ring size reference chart
Measurements below are approximate US-size conversions, rounded for reference. They are not a manufacturer-specific fit guarantee. Diameter means the distance across the inside of a ring; circumference means the distance around the inside. Both are measured in millimeters.
| US size | Inside diameter (mm) | Inside circumference (mm) |
|---|---|---|
| 0.5 | 12.04 | 37.8 |
| 1 | 12.44 | 39.1 |
| 1.5 | 12.85 | 40.4 |
| 2 | 13.26 | 41.6 |
| 2.5 | 13.66 | 42.9 |
| 3 | 14.07 | 44.2 |
| 3.5 | 14.47 | 45.5 |
| 4 | 14.88 | 46.8 |
| 4.5 | 15.29 | 48.0 |
| 5 | 15.69 | 49.3 |
| 5.5 | 16.10 | 50.6 |
| 6 | 16.51 | 51.9 |
| 6.5 | 16.91 | 53.1 |
| 7 | 17.32 | 54.4 |
| 7.5 | 17.73 | 55.7 |
| 8 | 18.13 | 57.0 |
| 8.5 | 18.54 | 58.2 |
| 9 | 18.95 | 59.5 |
| 9.5 | 19.35 | 60.8 |
| 10 | 19.76 | 62.1 |
| 10.5 | 20.16 | 63.3 |
| 11 | 20.57 | 64.6 |
| 11.5 | 20.98 | 65.9 |
| 12 | 21.38 | 67.2 |
| 12.5 | 21.79 | 68.5 |
| 13 | 22.20 | 69.7 |
| 13.5 | 22.60 | 71.0 |
| 14 | 23.01 | 72.3 |
Professional sizing
Ask a jeweler to measure the finger on which you will wear your ring using US ring sizers. Try a sizer with a similar band width to your chosen design. Wider bands may feel tighter than narrow bands.
At-home measurement
Use a non-stretch paper strip around the base of your finger. Mark where it overlaps, then measure the length in millimeters with a ruler. Compare this circumference with the chart. Repeat the measurement several times. Paper and string measurements can be inaccurate; confirm with a jeweler before ordering if possible.
Knuckle fit
Your ring should pass over your knuckle with gentle resistance and sit comfortably at the base without pinching. If your knuckle is noticeably larger than the base of your finger, ask a jeweler to help balance the fit.
When to measure
Measure when your hands are at a comfortable room temperature, preferably later in the day. Avoid measuring when your fingers are unusually cold, hot, or swollen after exercise. Check again on another day if measurements vary.
Between sizes
Do not round down to a tight fit. Try both neighboring sizes, especially for wider bands, and confirm which fits comfortably over your knuckle. Contact us before ordering if you are unsure.
Before ordering
Confirm your size and the design's available options before checkout. If you may need a future size adjustment, contact us to confirm whether resizing is possible for your chosen ring and what terms apply.
About printing
This chart is for reading measurements only. Do not use printed circles, page dimensions, or a cut-out strip to determine your size. No scale-tested printable sizing tool is included.