Cushion Cut Diamond Size Chart + Weight Calculator
Wondering how big a 1-carat Cushion Cut Diamond is or how much a 6x6mm Cushion Cut Diamond weighs?
Then you have come to the right page as I have created a full chart and built a really easy-to-use calculator to help you get an idea of how much your Diamond weighs.
Quick Note: These are estimated weights only, the actual weight of your Diamond may be different depending on the proportions of the stone.
Cushion Cut Diamond Weight Calculator
I have created charts for Cushion size to weights below but if you have the measurements of your Diamond, you can use my calculator.
Cushion Cut Size to Carat Chart
0.5 Carat = 4.6 x 4.6mm
0.75 Carats = 5.2 x 5.2mm
1 Carat = 5.8 x 5.8mm
2 Carat = 7.3 x 7.3mm
3 Carat = 8.3 x 8.3mm
Images are for illustration purposes only as it is very difficult to accurately represent image sizes on screens.
| Size | Weight |
|---|---|
| 3 x 3mm | 0.14ct |
| 3.1 x 3.1mm | 0.15ct |
| 3.2 x 3.2mm | 0.17ct |
| 3.3 x 3.3mm | 0.18ct |
| 3.4 x 3.4mm | 0.20ct |
| 3.5 x 3.5mm | 0.22ct |
| 3.6 x 3.6mm | 0.24ct |
| 3.7 x 3.7mm | 0.26ct |
| 3.8 x 3.8mm | 0.28ct |
| 3.9 x 3.9mm | 0.31ct |
| Size | Weight |
|---|---|
| 4 x 4mm | 0.33ct |
| 4.1 x 4.1mm | 0.35ct |
| 4.2 x 4.2mm | 0.38ct |
| 4.3 x 4.3mm | 0.41ct |
| 4.4 x 4.4mm | 0.44ct |
| 4.5 x 4.5mm | 0.47ct |
| 4.6 x 4.6mm | 0.50ct |
| 4.7 x 4.7mm | 0.54ct |
| 4.8 x 4.8mm | 0.57ct |
| 4.9 x 4.9mm | 0..61ct |
| Size | Weight |
|---|---|
| 5 x 5mm | 0.65ct |
| 5.1 x 5.1mm | 0.69ct |
| 5.2 x 5.2mm | 0.73ct |
| 5.3 x 5.3mm | 0.77ct |
| 5.4 x 5.4mm | 0.82ct |
| 5.5 x 5.5mm | 0.86ct |
| 5.6 x 5.6mm | 0.91ct |
| 5.7 x 5.7mm | 0.96ct |
| 5.8 x 5.8mm | 1.01ct |
| 5.9 x 5.9mm | 1.07ct |
| Size | Weight |
|---|---|
| 6 x 6mm | 1.12ct |
| 6.1 x 6.1mm | 1.18ct |
| 6.2 x 6.2mm | 1.24ct |
| 6.3 x 6.3mm | 1.30ct |
| 6.4 x 6.4mm | 1.36ct |
| 6.5 x 6.5mm | 1.43ct |
| 6.6 x 6.6mm | 1.49ct |
| 6.7 x 6.7mm | 1.57ct |
| 6.8 x 6.8mm | 1.63ct |
| 6.9 x 6.9mm | 1.71ct |
| Size | Weight |
|---|---|
| 7 x 7mm | 1.78ct |
| 7.1 x 7.1mm | 1.86ct |
| 7.2 x 7.2mm | 1.94ct |
| 7.3 x 7.3mm | 2.02ct |
| 7.4 x 7.4mm | 2.11ct |
| 7.5 x 7.5mm | 2.20ct |
| 7.6 x 7.6mm | 2.28ct |
| 7.7 x 7.7mm | 2.38ct |
| 7.8 x 7.8mm | 2.47ct |
| 7.9 x 7.9mm | 2.57ct |
| Size | Weight |
|---|---|
| 8 x 8mm | 2.67ct |
| 8.1 x 8.1mm | 2.77ct |
| 8.2 x 8.2mm | 2.87ct |
| 8.3 x 8.3mm | 2.98ct |
| 8.4 x 8.4mm | 3.09ct |
| 8.5 x 8.5mm | 3.20ct |
| 8.6 x 8.6mm | 3.31ct |
| 8.7 x 8.7mm | 3.43ct |
| 8.8 x 8.8mm | 3.55ct |
| 8.9 x 8.9mm | 3.68ct |
| Size | Weight |
|---|---|
| 9 x 9mm | 3.80ct |
| 9.1 x 9.1mm | 3.92ct |
| 9.2 x 9.2mm | 4.06ct |
| 9.3 x 9.3mm | 4.19ct |
| 9.4 x 9.4mm | 4.33ct |
| 9.5 x 9.5mm | 4.47ct |
| 9.6 x 9.6mm | 4.61ct |
| 9.7 x 9.7mm | 4.76ct |
| 9.8 x 9.8mm | 4.90ct |
| 9.9 x 9.9mm | 5.06ct |
| Size | Weight |
|---|---|
| 10 x 10mm | 5.21ct |
| 11 x 11mm | 6.94ct |
| 12 x 12mm | 9.01ct |
| 13 x 13mm | 11.46ct |
| 14 x 14mm | 14.31ct |
| 15 x 15mm | 17.60ct |
| 16 x 16mm | 21.36ct |
| 17 x 17mm | 25.62ct |
| 18 x 18mm | 30.42ct |
| 19 x 19mm | 35.77ct |
In the charts above, you will see that I have listed the size to weight of square Cushion Cuts and while there are a lot of these on the market, there are also elongated Cushion Cuts that can have a length-to-width ratio of 1:10 – 1:30 or more.
Due to the large number of variations within these different length-to-width, it simply isn’t possible to list the size to weight for these elongated shapes but you can use the calculator above for this.
And as with all size-to-weight charts, this should be used as a guide only as there are factors that impact the weight of a Cushion Cut Diamond, including:
- Girdle thickness
- Length-to-width ratio
- Pavilion angle
- Table size
Another issue with doing weight estimation for Cushion Cut Diamonds is that there aren’t any globally recognized ‘ideal’ proportions, which is why Cushion Cut Diamonds aren’t given a cut grade by gems labs such as the GIA.
This does make doing weight estimation for cut styles other than Round Brilliants more challenging but I hope that the charts and calculator above help to give you some idea as to how much your Diamond might weigh.
If you want to check the size-to-weight of other styles of cut, then you can use my full Diamond weight estimation calculator or check out my other size-to-weight charts below.
Other Diamond Size Charts
I'm Paul Haywood FGA DGA, the owner and founder of Haywoods Gems, I'm a fully qualified Gemmologist and Diamond Grader from the Gemmological Association of Great Britain.