How to measure your ring size at home
No jeweller needed. The most reliable home method measures the inner circumference in mm.
Method 1 — string or paper
Wrap a thin strip of paper or string snugly around the base of your finger. Mark the overlap, lay it flat, measure in mm. Match it to a ring chart.
Method 2 — a ring that fits
Measure the inside diameter of a ring that already fits, across the middle in mm. Often the most accurate method.
Ring size from circumference
| Circumference | Inner Ø | US size |
|---|---|---|
| 49.3 mm | 15.7 mm | 5 |
| 51.9 mm | 16.5 mm | 6 |
| 54.4 mm | 17.3 mm | 7 |
| 57.0 mm | 18.1 mm | 8 |
| 59.5 mm | 18.9 mm | 9 |
Measure at the end of the day; avoid measuring when cold. Between sizes? Size up — a slightly loose ring beats a stuck one.
Frequently asked questions
How do I measure ring size at home?
Wrap string around the finger, mark the overlap, measure in mm, match to a chart. Or measure the inside diameter of a ring that fits.
What is the best way to measure ring size?
Measuring the inside diameter of a well-fitting ring in mm is usually most accurate.
Should I size up if between ring sizes?
Yes — go up. A slightly loose ring is easier to wear than one that won't come off.