| METRIC SIZES | US SIZES | UK SIZES |
| 1mm | 5/0 | 19 |
| 1.25mm | 4/0 | 18 |
| 1.5mm | 000 | 17 |
| 1.75mm | 00 | 15 |
| 2.0mm | 0 | 14 |
| 2.25mm | 1 | 13 |
| 2.75mm | 2 | 12 |
| 3.0mm | - | 11 |
| 3.25mm | 3 | 10 |
| 3.5mm | 4 | - |
| 3.75mm | 5 | 9 |
| 4.0mm | 6 | 8 |
| 4.5mm | 7 | 7 |
| 5.0mm | 8 | 6 |
| 5.5mm | 9 | 5 |
| 6.0mm | 10 | 4 |
| 6.5mm | 10 1/2 | 3 |
| 7.0mm | - | 2 |
| 7.5mm | - | 1 |
| 8.0mm | 11 | 0 |
| 9.0mm | 13 | 00 |
| 9.5mm | 14 | - |
| 10.0mm | 15 | 000 |
| 12.0mm | 17 | - |
| 16.0 | 19 | - |
| 19.0 | 35 | - |
| 25.0 | 50 | - |