UK letters, EU numbers, millimetres
Size guide
UK ring sizes are letters, EU sizes are numbers. The EU number is simply the inside circumference of the ring in millimetres, so the two convert directly.
Sizes each finger usually takes
| Finger | Our widths | Usually UK | Usually EU | Sizes we make |
|---|---|---|---|---|
| Thumb RingsThumb | 5–8 mm | P–V | 57–65 | S · fits about UK N–R / L · fits about UK S–W |
| Index RingsIndex finger | face 8–14 mm | L–S | 51–60 | UK J½–Z½ |
| Middle RingsMiddle finger | 3–10 mm | L–T | 51–62 | UK J½–Z½ |
| Stacking BandsRing finger | 1–2 mm | J–Q | 49–57 | UK H½–X½ |
| Little Finger RingsLittle finger | 1.5–9 mm | G–N | 46–54 | UK F½–T½ |
| Knuckle RingsUpper knuckle | 1–1.5 mm | D–K | 42–50 | S · fits about UK D–G / M · fits about UK H–K |
| Hand ChainsBack of the hand | fine chain | J–P | 49–56 | Wrist 14–17 cm / Wrist 16–19 cm |
These are typical ranges for adults; your own hands may differ. A thumb is usually several letters larger than your ring finger, and your dominant hand is often half a size larger than the other.
UK, EU and millimetres
| UK | EU | Inner diameter | Inner circumference | US (approx.) |
|---|---|---|---|---|
| F | 44 | 13.9 mm | 43.6 mm | 2.75 |
| G | 45 | 14.3 mm | 44.8 mm | 3.25 |
| H | 46 | 14.7 mm | 46.1 mm | 3.75 |
| I | 47 | 15.1 mm | 47.4 mm | 4.25 |
| J | 49 | 15.5 mm | 48.7 mm | 4.75 |
| K | 50 | 15.9 mm | 49.9 mm | 5.25 |
| L | 51 | 16.3 mm | 51.2 mm | 5.75 |
| M | 52 | 16.7 mm | 52.5 mm | 6.25 |
| N | 54 | 17.1 mm | 53.8 mm | 6.75 |
| O | 55 | 17.5 mm | 55.0 mm | 7.25 |
| P | 56 | 17.9 mm | 56.3 mm | 7.75 |
| Q | 58 | 18.3 mm | 57.6 mm | 8.25 |
| R | 59 | 18.7 mm | 58.9 mm | 8.75 |
| S | 60 | 19.1 mm | 60.2 mm | 9.25 |
| T | 61 | 19.6 mm | 61.4 mm | 9.75 |
| U | 63 | 20.0 mm | 62.7 mm | 10.25 |
| V | 64 | 20.4 mm | 64.0 mm | 10.75 |
| W | 65 | 20.8 mm | 65.3 mm | 11.25 |
| X | 67 | 21.2 mm | 66.5 mm | 11.75 |
| Y | 68 | 21.6 mm | 67.8 mm | 12.25 |
| Z | 69 | 22.0 mm | 69.1 mm | 12.75 |
Ring size charts vary slightly between jewellers — by up to half a size. Our sizes follow the table above.
How to measure
With a ring you own
Use our ring sizer on screen, or measure the inside diameter of the ring across its widest point with a ruler, in millimetres, and find it in the table.
With a strip of paper
Wrap a thin strip of paper around the base of the finger, mark where it overlaps, and measure the length in millimetres. That is your inner circumference and your EU size.
Fit by type of ring
- Thumb rings are open at the back and come in two fits: S (about UK N–R) and L (about UK S–W). Ease the band gently once to fit, and avoid bending it back and forth, which weakens the metal.
- Wide bands and signets (6 mm and wider) fit more snugly than a fine band of the same size. If you are between sizes, choose the larger one.
- Stacking bands feel tighter worn together than one alone. For three or more, consider going up half a size.
- Knuckle rings sit above the first knuckle and are open, in two fits: S (about UK D–G) and M (about UK H–K). They slip off easily — take them off for work, washing up and handwashing.
- Hand chains have an open ring that adjusts gently (about UK J–P) and a bracelet with a lobster clasp and short extender, in two wrist sizes.
Not sure? Ask us before you order.