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 use the Cushion Cut Diamond size chart?
The chart helps you see how each carat weight translates into millimeter dimensions, so you can visualize the actual size of your cushion diamond before buying.
Do cushion diamonds hide inclusions well?
Yes, the facet pattern of a cushion cut helps mask small inclusions better than step-cut shapes like emeralds or Asschers.
How can I make my cushion diamond appear larger?
Choose a halo setting or a slightly elongated ratio (around 1.15) to give the illusion of a bigger stone on your finger.
What makes cushion cut diamonds so popular for vintage-style rings?
Their rounded corners and soft edges resemble old mine cuts, giving cushion diamonds a timeless, romantic appeal that fits both modern and vintage designs.
What’s the best color grade for cushion cut diamonds?
Since cushion cuts tend to retain more color, grades between G and I are ideal for balancing warmth and sparkle—especially in yellow or rose gold settings.
What is the ideal ratio for a cushion cut diamond?
A length-to-width ratio between 1.00 and 1.10 gives a square shape, while 1.15 to 1.30 creates a more rectangular look.
Are all cushion diamonds the same shape?
No, cushion diamonds vary from square to rectangular, and the exact shape depends on the length-to-width ratio and cutting style.
Terms & Conditions
Fascinating Diamonds supplies products listed on the Fascinating Diamonds, and Fascinating Diamonds websites, and in our stores under the following Terms and Conditions. Please read these Terms and Conditions, and our Privacy and Cookie Policies carefully before using any of our websites, or ordering from us.
The Terms and Conditions apply to your use of any Fascinating Diamonds website and to any products you purchase from them; regardless of how you access the website, including any technologies or devices where our website is available to you at home, on the move or in store
We reserve the right to update these Terms and Conditions at any time, and any updates affecting you or your purchases will be notified to you, by us in writing (via email), and on this page.
The headings in these Conditions are for convenience only and shall not affect their interpretation.
We recommend that you print and keep a copy of these Terms and Conditions for your future reference...