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.
Oval Cut Diamond Size Chart (MM)
The Oval cut diamond varies in length-to-width ratios like the Emerald cut diamond. The chart below compiles average conversions for the millimeter measurements and carat weight of oval cut diamonds.
| Oval MM Size | Oval Carat Weight |
|---|---|
| 4.5×3.5 mm. | 0.21 ct. |
| 5×3 mm. | 0.21 ct. |
| 5.5×3.5 mm. | 0.33 ct. |
| 5×4 mm. | 0.35 ct. |
| 6×4 mm. | 0.50 ct. |
| 6×5 mm. | 0.61 ct. |
| 6.5×4.5 mm. | 0.65 ct. |
| 7×5 mm. | 0.75 ct. |
| 7.7×5.7 mm. | 1.00 ct. |
| 8×6 mm. | 1.25 ct. |
| 9×6 mm. | 1.41 ct. |
| 8.5×6.5 mm. | 1.50 ct. |
| 9×7 mm. | 2.00 ct. |
| Oval MM Size | Oval Carat Weight |
|---|---|
| 10×8 mm. | 2.50 ct. |
| 10.5×8.5 mm. | 2.88 ct. |
| 12×8 mm. | 3.00 ct. |
| 11×9 mm. | 3.85 ct. |
| 12×10 mm. | 5.05 ct. |
| 14×10 mm. | 5.81 ct. |
| 13×11 mm. | 6.05 ct. |
| 14×12 mm. | 8.21 ct. |
| 15×12 mm. | 8.76 ct. |
| 16×12 mm. | 9.32 ct. |
| 16×14 mm. | 11.88 ct. |
| 18×13 mm. | 12.86 ct. |
| 20×15 mm. | 14.96 ct. |