

Cushion Diamond
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.
Is a cushion diamond a good choice?
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.
Why people love it
- +Exceptional fire, often displaying more colorful light dispersion than rounds
- +25-35% more affordable than comparable round brilliants
- +Soft, rounded corners reduce the risk of chipping
- +Versatile aesthetic that bridges vintage and modern design
- +Available in both square and elongated proportions to suit different tastes
Things to know
- −Shows color more readily than rounds, so you may need a higher color grade
- −Appears slightly smaller face-up than a round of equal carat weight
- −No standardized cut grade from labs. You need photos or video to judge quality.
- −The crushed ice vs. chunky distinction can be confusing when shopping
How big is a cushion diamond? (MM to carat)
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.
How to buy a cushion diamond
- •Decide between chunky and crushed ice sparkle patterns before shopping. They're fundamentally different looks.
- •Color shows more in cushions than rounds. Stay at H or above in white metal settings.
- •For square cushions, look for L/W ratios between 1.00 and 1.05; for elongated, 1.15-1.25
- •Check the depth percentage: stones over 68% depth will look smaller face-up than their carat weight suggests
- •VS2 clarity is typically eye-clean in cushions due to the facet pattern breaking up inclusions
- •Request video to evaluate the sparkle pattern. Photos alone can't convey the difference between chunky and crushed ice.
What makes a cushion diamond unique?
How much does a cushion diamond cost?
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 →Technical Specifications
- Facets
- 58
- Brilliance
- very high
- L:W Ratio
- 1.0:1 to 1.10:1 (square cushion) or 1.15:1 to 1.30:1 (elongated cushion)
Last updated: 2026-07-16
At a Glance
- Price vs Round
- 25-35% less than round brilliant
- Popularity
- Third most popular (approximately 8-10% of engagement ring sales)
- Sparkle
- very high
Best For
Setting Ideas
- Halo (the most popular pairing, emphasizes the pillow shape and adds perceived size)
- Solitaire with a thin, delicate band for a clean modern look
- Three-stone with trapezoid or half-moon side stones
- Vintage-inspired with milgrain and filigree details
- Pave band. Adds continuous sparkle that complements the cushion's fire.
- Cathedral setting. Elevates the stone and creates an elegant profile.