Diamond Size Chart
Radiant Diamond Size Chart
Radiant cut diamonds have trimmed corners and a brilliant cut style that blends round sparkle with an emerald-like outline.
Average Radiant Diamond Sizes
- 0.50 carat ≈ 5 x 4 mm
- 1.00 carat ≈ 6.5 x 5.5 mm
- 2.00 carat ≈ 8 x 7 mm
Tip: Rectangular radiants often look bigger than square ones of the same carat.
Select a diamond shape.
| MM Size | Carat Weight |
|---|---|
| 4.3x3 mm. | 0.25 ct. |
| 4.5x3.5 mm. | 0.34 ct. |
| 6x3 mm. | 0.41 ct. |
| 6x4 mm. | 0.50 ct. |
| 6.5x4.5 mm. | 0.75 ct. |
| 7x5 mm. | 1.00 ct. |
| 7.3x5.5 mm. | 1.25 ct. |
| 7.5x5.8 mm. | 1.50 ct. |
| 8x6 mm. | 1.75 ct. |
| MM Size | Carat Weight |
|---|---|
| 8.2x6.2 mm. | 2.00 ct. |
| 8.5x6.5 mm. | 2.25 ct. |
| 9x7 mm. | 2.50 ct. |
| 9.5x7.5 mm. | 3.00 ct. |
| 10x7 mm. | 3.31 ct. |
| 10x8 mm. | 3.50 ct. |
| 10.2x8.2 mm. | 4.00 ct. |
| 10.5x8.5 mm. | 4.50 ct. |
| 11x9 mm. | 5.00 ct. |
| MM Size | Carat Weight |
|---|---|
| 11.5x10 mm. | 6.45 ct. |
| 12x9 mm. | 6.06 ct. |
| 13x9 mm. | 6.54 ct. |
| 13.2x9.2 mm. | 6.79 ct. |
| 14x10 mm. | 8.47 ct. |
| 13x11 mm. | 9.33 ct. |
| 13.5x11.5 mm. | 10.19 ct. |
| 15x11 mm. | 11.48 ct. |
| 14x12 mm. | 12.14 ct. |
| 16x12 mm. | 14.22 ct. |
Frequently Asked Questions
How do I read the Oval Cut Diamond size chart?
The chart lists the millimeter measurements that correspond to each carat weight, helping you understand the actual size of your oval diamond before purchase.
Are oval diamonds larger than round diamonds of the same carat?
Yes, oval diamonds often appear larger because of their elongated shape, which gives more visible surface area compared to round diamonds of equal carat weight.
What is the ideal ratio for an oval cut diamond?
A length-to-width ratio between 1.35 and 1.50 is generally considered ideal, offering a balanced, elegant look.
Does the size of an oval diamond affect its sparkle?
Yes, larger oval diamonds can show a “bow-tie effect,” which slightly affects brilliance. Choosing a well-cut stone minimizes this effect.
What size oval diamond is best for an engagement ring?
Oval diamonds between 1.0 and 2.0 carats are most popular for engagement rings, offering a perfect balance between size and sparkle.
How can I visualize the oval diamond size on my hand?
Use the millimeter dimensions from the chart to compare against your ring finger or try online visualization tools to estimate the fit and look.
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