Diamonds can be measured in both carat weight and millimeter. While diamonds are purchased based on carat weight — the standard unit of measurement for loose diamonds — it’s important to consider millimeter measurements and ratios to choose the best possible option for your budget.
Cushion Cut Diamond Size Chart (MM)
Cushion cut diamonds are one of the hardest shapes to predict size based on weight or millimeter measurements. Use our cushion diamond size chart to see how it would look on a hand.
| Round MM Size | Round Carat Weight |
|---|---|
| 0.8 mm. | 0.0025 ct. |
| 1 mm. | 0.005 ct. |
| 1.1 mm. | 0.0067 ct. |
| 1.2 mm. | 0.009 ct. |
| 1.25 mm. | 0.01 ct. |
| 1.3 mm. | 0.01 ct. |
| 1.5 mm. | 0.015 ct. |
| 1.75 mm. | 0.02 ct. |
| 1.8 mm. | 0.025 ct. |
| 2 mm. | 0.03 ct. |
| 2.2 mm. | 0.04 ct. |
| 2.5 mm. | 0.06 ct. |
| 2.75 mm. | 0.08 ct. |
| 3 mm. | 0.10 ct. |
| 3.25 mm. | 0.14 ct. |
| 3.5 mm. | 0.17 ct. |
| 3.75 mm. | 0.21 ct. |
| 4 mm. | 0.25 ct. |
| 4.25 mm. | 0.28 ct. |
| 4.5 mm. | 0.36 ct. |
| 4.75 mm. | 0.44 ct. |
| 5.0 mm. | 0.50 ct. |
| 5.25 mm. | 0.56 ct. |
| 5.5 mm. | 0.66 ct. |
| 5.75 mm. | 0.75 ct. |
| 6 mm. | 0.84 ct. |
| 6.25 mm. | 0.93 ct. |
| 6.5 mm. | 1.00 ct. |
| 6.8 mm. | 1.25 ct. |
| Round MM Size | Round Carat Weight |
|---|---|
| 7 mm. | 1.30 ct. |
| 7.3 mm. | 1.50 ct. |
| 7.5 mm. | 1.67 ct. |
| 7.75 mm. | 1.75 ct. |
| 8 mm. | 2.00 ct. |
| 8.25 mm. | 2.11 ct. |
| 8.5 mm. | 2.43 ct. |
| 8.7 mm. | 2.50 ct. |
| 9 mm. | 2.75 ct. |
| 9.1 mm. | 3.00 ct. |
| 9.5 mm. | 3.35 ct. |
| 9.75 mm. | 3.61 ct. |
| 10 mm. | 3.87 ct. |
| 10.25 mm. | 4.16 ct. |
| 10.5 mm. | 4.41 ct. |
| 10.75 mm. | 4.57 ct. |
| 11 mm. | 4.91 ct. |
| 11.25 mm. | 5.49 ct. |
| 11.5 mm. | 5.85 ct. |
| 12 mm. | 6.84 ct. |
| 12.25 mm. | 7.26 ct. |
| 12.5 mm. | 7.36 ct. |
| 12.75 mm. | 7.52 ct. |
| 13 mm. | 8.51 ct. |
| 13.5 mm. | 9.53 ct. |
| 14 mm. | 10.49 ct. |
| 15 mm. | 12.89 ct. |
| 16 mm. | 16.06 ct. |