At the same weight a oval covers about 8% more of the finger. Same carat, same price bracket, visibly different stone.
The reason is proportion, not quality. A oval runs about 1.40:1 long to wide; a round about 1.00:1. Weight spent on length is weight you can see. Weight spent on depth sits below the setting, where it does nothing for appearance.
| Carat | Oval (mm) | Oval area | Round (mm) | Round area |
|---|---|---|---|---|
| 0.25 ct | 4.99 × 3.56 | 13.9 | 4.05 × 4.05 | 12.9 |
| 0.5 ct | 6.28 × 4.49 | 22.1 | 5.11 × 5.11 | 20.5 |
| 0.75 ct | 7.19 × 5.14 | 29.0 | 5.85 × 5.85 | 26.8 |
| 1 ct | 7.91 × 5.65 | 35.1 | 6.44 × 6.44 | 32.5 |
| 1.25 ct | 8.53 × 6.09 | 40.8 | 6.93 × 6.93 | 37.7 |
| 1.5 ct | 9.06 × 6.47 | 46.0 | 7.37 × 7.37 | 42.6 |
| 2 ct | 9.97 × 7.12 | 55.8 | 8.11 × 8.11 | 51.6 |
| 2.5 ct | 10.74 × 7.67 | 64.7 | 8.73 × 8.73 | 59.9 |
| 3 ct | 11.41 × 8.15 | 73.1 | 9.28 × 9.28 | 67.6 |
An elongated shape also reads longer on the finger, which is a separate question from area. Whether that suits a particular hand is not something a table can settle — which is exactly why it is worth putting the two on your own photograph, at the same scale, and looking.