Buying a ring online or from abroad means you need to know your ring size in the right system. Different countries use completely different sizing systems, but this guide makes conversion simple.
How to Measure Your Ring Size at Home
Method 1: String or Paper Strip
- Cut a thin strip of paper or use a piece of string (about 10cm long)
- Wrap it around the base of your finger snugly (not too tight)
- Mark where the strip overlaps with a pen
- Measure the length from the end to the mark in millimetres
- This is your finger circumference — use the table below to find your size
Method 2: Measure an Existing Ring
Place a ring you already own on a ruler. Measure the internal diameter in millimetres. Use the table below to find your size.
Ring Size Conversion Chart
| Diameter (mm) | Circumference (mm) | US Size | UK Size | EU Size |
|---|---|---|---|---|
| 15.7 mm | 49.3 mm | 5 | J½ | 49 |
| 16.5 mm | 51.9 mm | 6 | L½ | 52 |
| 17.3 mm | 54.4 mm | 7 | N½ | 54 |
| 18.2 mm | 57.0 mm | 8 | P½ | 57 |
| 19.0 mm | 59.5 mm | 9 | R½ | 60 |
| 19.8 mm | 62.1 mm | 10 | T½ | 62 |
Tips for Accurate Measurement
- Measure in the evening — fingers are slightly larger later in the day and when warm
- Measure the correct finger — fingers on your dominant hand are typically slightly larger
- Consider the knuckle — if your knuckle is wider than your finger base, size up slightly
- Measure 2–3 times — take the average for accuracy
Average Ring Sizes
Average women's ring size: US 6–7 (UK M–O, EU 52–54). Average men's ring size: US 9–10 (UK R–T, EU 60–63). These are averages only — always measure before ordering.