| AU | US |
| A | 1/2 |
| A 1/2 | 3/4 |
| B | 1 |
| B 1/2 | 1 1/4 |
| C | 1 1/2 |
| C 1/2 | 1 3/4 |
| D | 2 |
| D 1/2 | 2 1/4 |
| E | 2 1/2 |
| E 1/2 | 2 3/4 |
| F | 3 |
| F 1/2 | 3 1/8 |
| F 3/4 | 3 1/4 |
| G | 3 3/8 |
| G 1/4 | 3 1/2 |
| G 1/2 | 3 5/8 |
| H | 3 3/4 |
| H 1/2 | 4 |
| I | 4 1/4 |
| I 1/2 | 4 1/2 |
| J | 4 5/8 |
| J 1/4 | 4 3/4 |
| J 1/2 | 5 |
| K | 5 1/8 |
| K 1/4 | 5 1/4 |
| K 1/2 | 5 3/8 |
| L | 5 1/2 |
| L 1/4 | 5 3/4 |
| L 1/2 | 5 7/8 |
| M | 6 |
| M 1/2 | 6 1/4 |
| N | 6 1/2 |
| N 1/2 | 6 3/4 |
| O | 7 |
| O 1/2 | 7 1/4 |
| P | 7 1/2 |
| P 1/2 | 7 3/4 |
| Q | 8 |
| Q 1/2 | 8 1/4 |
| Q 3/4 | 8 1/2 |
| R | 8 5/8 |
| R 1/4 | 8 3/4 |
| R 1/2 | 8 7/8 |
| R 3/4 | 9 |
| S | 9 1/8 |
| S 1/4 | 9 1/4 |
| S 1/2 | 9 3/8 |
| S 3/4 | 9 1/2 |
| T | 9 5/8 |
| T 1/4 | 9 3/4 |
| T 1/2 | 10 |
| U | 10 1/4 |
| U 1/2 | 10 1/2 |
| V | 10 5/8 |
| V 1/4 | 10 3/4 |
| V 1/2 | 11 |
| W | 11 1/8 |
| W 1/4 | 11 1/4 |
| W 1/2 | 11 3/8 |
| W 3/4 | 11 1/2 |
| X | 11 5/8 |
| X 1/4 | 11 3/4 |
| X 1/2 | 11 7/8 |
| Y | 12 |
| Y 1/2 | 12 1/4 |
| Z | 12 1/2 |
| Z +1/2 | 12 3/4 |
| Z+1 | 13 |
| Z+1.5 | 13 1/2 |

| Fraction | Carat weight |
| 9/10 | 0.90 – 0.95 |
| 7/8 | 0.84 – 0.89 |
| 3/4 | 0.70 – 0.83 |
| 5/8 | 0.57 – 0.69 |
| 1/2 | 0.47 – 0.56 |
| 3/8 | 0.38 – 0.46 |
| 1/3 | 0.30 – 0.37 |
| 1/4 | 0.23 – 0.29 |
| 1/5 | 0.18 – 0.22 |
| 1/6 | 0.15 – 0.17 |
| 1/8 | 0.12 – 0.14 |
| 1/10 | 0.09 – 0.11 |
