

The cushion cut features soft, rounded corners with a square or rectangular outline, resembling a pillow. It blends vintage charm with modern brilliance, offering exceptional fire and a distinctive chunky sparkle pattern.
Cushion diamonds are known for very high brilliance with 58 facets. They're popular for engagement rings and halo settings. Here are the trade-offs.
A 1-carat cushion diamond measures approximately 5.8 x 5.8 mm. Here are the most common sizes from 0.25 ct to 5 ct.
| Carat Weight | Size (mm) |
|---|---|
| 0.25 ct | 3.5 x 3.5 mm |
| 0.33 ct | 3.8 x 3.8 mm |
| 0.5 ct | 4.5 x 4.5 mm |
| 0.75 ct | 5.2 x 5.2 mm |
| 1 ct | 5.8 x 5.8 mm |
| 1.25 ct | 6.2 x 6.2 mm |
| 1.5 ct | 6.7 x 6.7 mm |
| 2 ct | 7.3 x 7.3 mm |
| 2.5 ct | 7.8 x 7.8 mm |
| 3 ct | 8.2 x 8.2 mm |
| 4 ct | 9.0 x 9.0 mm |
| 5 ct | 9.8 x 9.8 mm |
View full cushion size chart → with all sizes from melee to 5+ carats.
Cushion diamonds are priced at 25-35% less than round brilliant. Price depends on carat weight, color, clarity, and cut quality. For a personalized estimate, use our diamond price estimator.
Estimate cushion diamond price →Last updated: 2026-07-16