Dimension to Carat
Here are top general guidelines for converting diamond dimensions (measured in millimeters) to carat weight for common diamond shapes:
| Millimeter (mm) | Carat (ct) |
|---|---|
| 0.8mm | 0.0025ct |
| 1mm | 0.005ct |
| 1.1mm | 0.0067ct |
| 1.2mm | 0.009ct |
| 1.25mm | 0.01ct |
| 1.3mm | 0.01ct |
| 1.5mm | 0.015ct |
| 1.75mm | 0.02ct |
| 1.8mm | 0.025ct |
| 2mm | 0.03ct |
| 2.2mm | 0.04ct |
| 2.5mm | 0.06ct |
| 2.75mm | 0.08ct |
| 3mm | 0.10ct |
| 3.25mm | 0.14ct |
| 3.5mm | 0.17ct |
| 3.75mm | 0.21ct |
| 4mm | 0.25ct |
| 4.25mm | 0.28ct |
| 4.5mm | 0.36ct |
| 4.75mm | 0.44ct |
| 5.0mm | 0.50ct |
| 5.25mm | 0.56ct |
| 5.5mm | 0.66ct |
| 5.75mm | 0.75ct |
| 6mm | 0.84ct |
| 6.25mm | 0.93ct |
| 6.5mm | 1.00ct |
| 6.8mm | 1.25ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 7mm | 1.30ct |
| 7.3mm | 1.50ct |
| 7.5mm | 1.67ct |
| 7.75mm | 1.75ct |
| 8mm | 2.00ct |
| 8.25mm | 2.11ct |
| 8.5mm | 2.43ct |
| 8.7mm | 2.50ct |
| 9mm | 2.75ct |
| 9.1mm | 3.00ct |
| 9.5mm | 3.35ct |
| 9.75mm | 3.61ct |
| 10mm | 3.87ct |
| 10.25mm | 4.16ct |
| 10.5mm | 4.41ct |
| 10.75mm | 4.57ct |
| 11mm | 4.91ct |
| 11.25mm | 5.49ct |
| 11.5mm | 5.85ct |
| 12mm | 6.84ct |
| 12.25mm | 7.26ct |
| 12.5mm | 7.36ct |
| 12.75mm | 7.52ct |
| 13mm | 8.51ct |
| 13.5mm | 9.53ct |
| 14mm | 10.49ct |
| 15mm | 12.89ct |
| 16mm | 16.06ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 4.2mm | 0.40ct |
| 4.9mm | 0.50ct |
| 5.25mm | 0.75ct |
| 5.5mm | 1.00ct |
| 6mm | 1.25ct |
| 6.5mm | 1.50ct |
| 7mm | 2.00ct |
| 7.5mm | 2.50ct |
| 8mm | 3.00ct |
| 8.5mm | 3.50ct |
| 9mm | 4.12ct |
| 9.5mm | 5.09ct |
| 10mm | 5.62ct |
| 11mm | 7.44ct |
| 12mm | 9.52ct |
| 13mm | 12.66ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 3.6×2.7mm | 0.10ct |
| 4x3mm | 0.15ct |
| 4.5×3.5mm | 0.20ct |
| 5×3.5mm | 0.25ct |
| 5.5×3.5mm | 0.33ct |
| 5x4mm | 0.35ct |
| 6x4mm | 0.50ct |
| 6x5mm | 0.61ct |
| 6.5×4.5mm | 0.65ct |
| 7x5mm | 0.75ct |
| 7.7×5.7mm | 1.00ct |
| 8x6mm | 1.25ct |
| 9x6mm | 1.41ct |
| 8.5×6.5mm | 1.50ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 9x7mm | 2.00ct |
| 10x8mm | 2.50ct |
| 10.5×8.5mm | 2.88ct |
| 12x8mm | 3.00ct |
| 11x9mm | 3.85ct |
| 12x10mm | 5.05ct |
| 14x10mm | 5.81ct |
| 13x11mm | 6.05ct |
| 14x12mm | 8.21ct |
| 15x12mm | 8.76ct |
| 16x12mm | 9.32ct |
| 16x14mm | 11.88ct |
| 18x13mm | 12.86ct |
| 20x15mm | 14.96ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 3x2mm | 0.13ct |
| 4×2.5mm | 0.18ct |
| 4x3mm | 0.21ct |
| 5x3mm | 0.25ct |
| 5x4mm | 0.35ct |
| 6x4mm | 0.50ct |
| 6.5×4.5mm | 0.60ct |
| 7x5mm | 0.75ct |
| 7.5×5.5mm | 0.85ct |
| 7.7×5.7mm | 1.00ct |
| 8x6mm | 1.25ct |
| 8.5×6.5mm | 1.50ct |
| 10x6mm | 1.71ct |
| 8.7×6.7mm | 1.80ct |
| 9x7mm | 2.00ct |
| 10x8mm | 2.50ct |
| 11×7.50mm | 2.61ct |
| 11x8mm | 2.70ct |
| 12x8mm | 3.00ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 12x7mm | 3.12ct |
| 13x8mm | 3.40ct |
| 12x9mm | 3.44ct |
| 14x8mm | 4.00ct |
| 13x9mm | 4.11ct |
| 14x9mm | 4.25ct |
| 15x9mm | 5.06ct |
| 14x10mm | 5.41ct |
| 13x11mm | 5.65ct |
| 15x10mm | 5.75ct |
| 16x9mm | 5.86ct |
| 16x10mm | 6.27ct |
| 17x10mm | 6.46ct |
| 15x11mm | 7.36ct |
| 18x11mm | 8.14ct |
| 16x12mm | 8.99ct |
| 18x12mm | 9.35ct |
| 18x13mm | 10.21ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 3x2mm | 0.10ct |
| 3.5x2mm | 0.12ct |
| 4x2mm | 0.15ct |
| 4x3mm | 0.20ct |
| 5x3mm | 0.29ct |
| 5.5×3.5mm | 0.46ct |
| 6x4mm | 0.50ct |
| 6.5×4.5mm | 0.75ct |
| 6.7×4.5mm | 0.88ct |
| 7x5mm | 1.00ct |
| 7.3×5.3mm | 1.25ct |
| 7.5×5.5mm | 1.50ct |
| 8x6mm | 1.75ct |
| 8.5×6.5mm | 2.00ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 9x7mm | 2.50ct |
| 10×7.5mm | 3.00ct |
| 9.5×7.5mm | 3.21ct |
| 10x8mm | 3.79ct |
| 11x9mm | 5.21ct |
| 12x8mm | 5.34ct |
| 12x10mm | 6.00ct |
| 14x8mm | 6.25ct |
| 13x9mm | 6.38ct |
| 14x10mm | 8.48ct |
| 13x11mm | 9.13ct |
| 14x12mm | 11.26ct |
| 16x12mm | 14.22ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 1.5mm | 0.015ct |
| 1.75mm | 0.03ct |
| 2mm | 0.06ct |
| 2.25mm | 0.08ct |
| 2.5mm | 0.10ct |
| 2.75mm | 0.13ct |
| 3mm | 0.18ct |
| 3.25mm | 0.26ct |
| 3.5mm | 0.29ct |
| 3.75mm | 0.31ct |
| 4mm | 0.39ct |
| 4.25mm | 0.44ct |
| 4.5mm | 0.50ct |
| 4.75mm | 0.64ct |
| 5mm | 0.75ct |
| 5.25mm | 0.90ct |
| 5.5mm | 1.00ct |
| 5.75mm | 1.11ct |
| 6mm | 1.25ct |
| 6.25mm | 1.39ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 6.5mm | 1.50ct |
| 6.75mm | 1.75ct |
| 7mm | 2.00ct |
| 7.25mm | 2.01ct |
| 7.5mm | 2.50ct |
| 7.75mm | 2.74ct |
| 8mm | 3.00ct |
| 8.25mm | 3.24ct |
| 8.5mm | 3.67ct |
| 8.75mm | 4.10ct |
| 9mm | 4.12ct |
| 9.5mm | 5.09ct |
| 9.75mm | 5.36ct |
| 10mm | 5.62ct |
| 10.25mm | 5.76ct |
| 10.5mm | 5.99ct |
| 11mm | 7.44ct |
| 11.5mm | 9.44ct |
| 12mm | 9.52ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 5x3mm | 0.31ct |
| 4.5×3.5mm | 0.34ct |
| 6x3mm | 0.41ct |
| 6x4mm | 0.50ct |
| 6.5×4.5mm | 0.75ct |
| 7x5mm | 1.00ct |
| 7.3×5.5mm | 1.25ct |
| 7.5×5.8mm | 1.50ct |
| 8x6mm | 2.00ct |
| 8.5×6.5mm | 2.25ct |
| 9x7mm | 2.50ct |
| 9.5×7.5mm | 3.00ct |
| 10x7mm | 3.31ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 10x8mm | 3.50ct |
| 11x9mm | 5.05ct |
| 12x9mm | 6.06ct |
| 11.5x10mm | 6.45ct |
| 13x9mm | 6.54ct |
| 12x10mm | 6.79ct |
| 14x10mm | 8.47ct |
| 13x11mm | 9.33ct |
| 13.5×11.5mm | 10.19ct |
| 15x11mm | 11.48ct |
| 14x12mm | 12.14ct |
| 16x12mm | 14.22ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 3×1.5mm | 0.025ct |
| 3.5×1.75mm | 0.065ct |
| 3.5x2mm | 0.07ct |
| 4x2mm | 0.10ct |
| 3.75×1.75mm | 0.11ct |
| 4.25×2.25mm | 0.12ct |
| 5×2.5mm | 0.14ct |
| 5.5×2.75mm | 0.16ct |
| 5.5x3mm | 0.18ct |
| 5x3mm | 0.20ct |
| 6.5x3mm | 0.23ct |
| 6x3mm | 0.25ct |
| 7x3mm | 0.30ct |
| 7.5×3.5mm | 0.33ct |
| 7x4mm | 0.34ct |
| 8x4mm | 0.50ct |
| 8.75×4.25mm | 0.70ct |
| 9×4.5mm | 0.75ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 9.5×4.7mm | 0.85ct |
| 10x5mm | 1.00ct |
| 11×5.5mm | 1.25ct |
| 11.5x6mm | 1.33ct |
| 12x6mm | 1.50ct |
| 13×6.5mm | 2.00ct |
| 14x7mm | 2.50ct |
| 15x7mm | 3.00ct |
| 14x8mm | 3.00ct |
| 15×7.5mm | 3.25ct |
| 15x8mm | 3.44ct |
| 16x8mm | 3.86ct |
| 16.5×8.25mm | 4.00ct |
| 17×8.5mm | 4.88ct |
| 17.5x10mm | 5.50ct |
| 20x8mm | 7.08ct |
| 20x10mm | 7.94ct |
| 20x11mm | 9.50ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 3.5mm | 0.18ct |
| 4mm | 0.25ct |
| 4.25mm | 0.28ct |
| 4.5mm | 0.34ct |
| 4.75mm | 0.38ct |
| 5mm | 0.50ct |
| 5.5mm | 0.61ct |
| 6mm | 0.75ct |
| 6.25mm | 0.83ct |
| 6.5mm | 1.00ct |
| 7mm | 1.25ct |
| 7.5mm | 1.50ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 8mm | 2.00ct |
| 8.5mm | 2.50ct |
| 9mm | 3.00ct |
| 10mm | 3.50ct |
| 11mm | 4.41ct |
| 12mm | 5.66ct |
| 13mm | 7.88ct |
| 14mm | 9.38ct |
| 15mm | 10.79ct |
| 16mm | 13.27ct |
| 18mm | 15.33ct |
| Millimeter (mm) | Carat (ct) |
|---|---|
| 4mm | 0.39ct |
| 4.5mm | 0.50ct |
| 5mm | 0.75ct |
| 5.5mm | 1.00ct |
| 6mm | 1.25ct |
| 6.5mm | 1.50ct |
| 7mm | 2.00ct |
| 7.5mm | 2.50ct |
| 8mm | 3.00ct |
| 8.5mm | 3.50ct |
| 9mm | 4.12ct |
| 9.5mm | 5.09ct |
| 10mm | 5.62ct |
| 11mm | 7.44ct |
| 12mm | 9.52ct |
| 13mm | 12.66ct |
Note that these are general guidelines and may vary slightly depending on the specific cut and proportions of the diamond. It’s always best to consult with a diamond expert to determine the exact carat weight of a diamond based on its dimensions.
