Understanding diamond carat weight and how it translates to actual size is essential when choosing your perfect lab grown diamond. Use our comprehensive size chart below to visualize how different carat weights appear across all popular diamond shapes.
Round Cut Diamond Size Chart
| Carat Weight |
Diameter (mm) |
Carat Weight |
Diameter (mm) |
| 0.01 ct |
1.3 mm |
0.50 ct |
5.2 mm |
| 0.03 ct |
2.0 mm |
0.75 ct |
5.9 mm |
| 0.05 ct |
2.5 mm |
1.00 ct |
6.5 mm |
| 0.10 ct |
3.0 mm |
1.25 ct |
7.0 mm |
| 0.15 ct |
3.4 mm |
1.50 ct |
7.4 mm |
| 0.20 ct |
3.8 mm |
2.00 ct |
8.2 mm |
| 0.25 ct |
4.1 mm |
2.50 ct |
8.9 mm |
| 0.30 ct |
4.4 mm |
3.00 ct |
9.4 mm |
| 0.40 ct |
4.8 mm |
4.00 ct |
10.3 mm |
| 0.45 ct |
5.0 mm |
5.00 ct |
11.1 mm |
|
10.00 ct |
14.0 mm |
Princess Cut Diamond Size Chart
| Carat Weight |
Length × Width (mm) |
Carat Weight |
Length × Width (mm) |
| 0.01 ct |
1.5 × 1.5 mm |
0.50 ct |
4.5 × 4.5 mm |
| 0.03 ct |
2.0 × 2.0 mm |
0.75 ct |
5.3 × 5.3 mm |
| 0.05 ct |
2.5 × 2.5 mm |
1.00 ct |
5.5 × 5.5 mm |
| 0.10 ct |
3.0 × 3.0 mm |
1.25 ct |
6.0 × 6.0 mm |
| 0.15 ct |
3.3 × 3.3 mm |
1.50 ct |
6.5 × 6.5 mm |
| 0.20 ct |
3.5 × 3.5 mm |
2.00 ct |
7.0 × 7.0 mm |
| 0.25 ct |
3.8 × 3.8 mm |
2.50 ct |
7.5 × 7.5 mm |
| 0.30 ct |
4.0 × 4.0 mm |
3.00 ct |
8.0 × 8.0 mm |
| 0.40 ct |
4.3 × 4.3 mm |
4.00 ct |
8.8 × 8.8 mm |
| 0.45 ct |
4.4 × 4.4 mm |
5.00 ct |
9.5 × 9.5 mm |
|
10.00 ct |
12.0 × 12.0 mm |
Cushion Cut Diamond Size Chart
| Carat Weight |
Length × Width (mm) |
Carat Weight |
Length × Width (mm) |
| 0.01 ct |
1.5 × 1.5 mm |
0.50 ct |
4.8 × 4.8 mm |
| 0.03 ct |
2.2 × 2.2 mm |
0.75 ct |
5.5 × 5.5 mm |
| 0.05 ct |
2.6 × 2.6 mm |
1.00 ct |
6.0 × 6.0 mm |
| 0.10 ct |
3.2 × 3.2 mm |
1.25 ct |
6.5 × 6.5 mm |
| 0.15 ct |
3.6 × 3.6 mm |
1.50 ct |
6.8 × 6.8 mm |
| 0.20 ct |
3.9 × 3.9 mm |
2.00 ct |
7.5 × 7.5 mm |
| 0.25 ct |
4.2 × 4.2 mm |
2.50 ct |
8.0 × 8.0 mm |
| 0.30 ct |
4.5 × 4.5 mm |
3.00 ct |
8.5 × 8.5 mm |
| 0.40 ct |
4.7 × 4.7 mm |
4.00 ct |
9.3 × 9.3 mm |
| 0.45 ct |
4.8 × 4.8 mm |
5.00 ct |
10.0 × 10.0 mm |
|
10.00 ct |
12.6 × 12.6 mm |
Emerald Cut Diamond Size Chart
| Carat Weight |
Length × Width (mm) |
Carat Weight |
Length × Width (mm) |
| 0.01 ct |
2.0 × 1.5 mm |
0.50 ct |
6.0 × 4.0 mm |
| 0.03 ct |
2.8 × 2.0 mm |
0.75 ct |
6.8 × 4.8 mm |
| 0.05 ct |
3.3 × 2.3 mm |
1.00 ct |
7.5 × 5.5 mm |
| 0.10 ct |
4.0 × 3.0 mm |
1.25 ct |
8.0 × 5.8 mm |
| 0.15 ct |
4.5 × 3.3 mm |
1.50 ct |
8.5 × 6.0 mm |
| 0.20 ct |
5.0 × 3.5 mm |
2.00 ct |
9.3 × 6.5 mm |
| 0.25 ct |
5.3 × 3.8 mm |
2.50 ct |
10.0 × 7.0 mm |
| 0.30 ct |
5.6 × 4.0 mm |
3.00 ct |
10.5 × 7.5 mm |
| 0.40 ct |
5.8 × 4.0 mm |
4.00 ct |
11.5 × 8.3 mm |
| 0.45 ct |
5.9 × 4.0 mm |
5.00 ct |
12.5 × 9.0 mm |
|
10.00 ct |
15.8 × 11.3 mm |
Pear Cut Diamond Size Chart
| Carat Weight |
Length × Width (mm) |
Carat Weight |
Length × Width (mm) |
| 0.01 ct |
2.3 × 1.5 mm |
0.50 ct |
6.5 × 4.5 mm |
| 0.03 ct |
3.0 × 2.0 mm |
0.75 ct |
7.5 × 5.0 mm |
| 0.05 ct |
3.5 × 2.5 mm |
1.00 ct |
8.5 × 5.5 mm |
| 0.10 ct |
4.5 × 3.0 mm |
1.25 ct |
9.0 × 6.0 mm |
| 0.15 ct |
5.0 × 3.5 mm |
1.50 ct |
9.8 × 6.5 mm |
| 0.20 ct |
5.5 × 3.8 mm |
2.00 ct |
10.8 × 7.0 mm |
| 0.25 ct |
6.0 × 4.0 mm |
2.50 ct |
11.5 × 7.5 mm |
| 0.30 ct |
6.3 × 4.3 mm |
3.00 ct |
12.0 × 8.0 mm |
| 0.40 ct |
6.5 × 4.5 mm |
4.00 ct |
13.0 × 8.8 mm |
| 0.45 ct |
6.5 × 4.5 mm |
5.00 ct |
14.0 × 9.5 mm |
|
10.00 ct |
17.6 × 11.8 mm |
Heart Cut Diamond Size Chart
| Carat Weight |
Length × Width (mm) |
Carat Weight |
Length × Width (mm) |
| 0.01 ct |
1.8 × 1.8 mm |
0.50 ct |
5.5 × 5.5 mm |
| 0.03 ct |
2.5 × 2.5 mm |
0.75 ct |
6.3 × 6.3 mm |
| 0.05 ct |
3.0 × 3.0 mm |
1.00 ct |
6.8 × 6.8 mm |
| 0.10 ct |
3.8 × 3.8 mm |
1.25 ct |
7.3 × 7.3 mm |
| 0.15 ct |
4.3 × 4.3 mm |
1.50 ct |
7.8 × 7.8 mm |
| 0.20 ct |
4.6 × 4.6 mm |
2.00 ct |
8.5 × 8.5 mm |
| 0.25 ct |
5.0 × 5.0 mm |
2.50 ct |
9.0 × 9.0 mm |
| 0.30 ct |
5.3 × 5.3 mm |
3.00 ct |
9.5 × 9.5 mm |
| 0.40 ct |
5.5 × 5.5 mm |
4.00 ct |
10.5 × 10.5 mm |
| 0.45 ct |
5.5 × 5.5 mm |
5.00 ct |
11.3 × 11.3 mm |
|
10.00 ct |
14.2 × 14.2 mm |
Radiant Cut Diamond Size Chart
| Carat Weight |
Length × Width (mm) |
Carat Weight |
Length × Width (mm) |
| 0.01 ct |
1.8 × 1.5 mm |
0.50 ct |
5.3 × 4.5 mm |
| 0.03 ct |
2.5 × 2.0 mm |
0.75 ct |
6.0 × 5.0 mm |
| 0.05 ct |
3.0 × 2.5 mm |
1.00 ct |
6.5 × 5.5 mm |
| 0.10 ct |
3.8 × 3.0 mm |
1.25 ct |
7.0 × 5.8 mm |
| 0.15 ct |
4.3 × 3.5 mm |
1.50 ct |
7.3 × 6.0 mm |
| 0.20 ct |
4.6 × 3.8 mm |
2.00 ct |
8.0 × 6.5 mm |
| 0.25 ct |
5.0 × 4.0 mm |
2.50 ct |
8.5 × 7.0 mm |
| 0.30 ct |
5.3 × 4.3 mm |
3.00 ct |
9.0 × 7.5 mm |
| 0.40 ct |
5.3 × 4.5 mm |
4.00 ct |
10.0 × 8.3 mm |
| 0.45 ct |
5.3 × 4.5 mm |
5.00 ct |
10.8 × 9.0 mm |
|
10.00 ct |
13.5 × 11.3 mm |
Understanding Carat Weight vs. Size
Carat weight measures how much a diamond weighs, not its physical size. Two diamonds of the same carat weight can appear different in size depending on their cut quality and proportions. Lab grown diamonds have identical physical properties to natural diamonds, so these measurements apply equally to both.
Key Points to Remember:
-
Cut Quality Matters: A well-cut diamond will appear larger and more brilliant than a poorly cut diamond of the same carat weight.
-
Shape Affects Appearance: Elongated shapes like pear, emerald, and oval can appear larger than round diamonds of the same carat weight.
-
Setting Style: The right setting can make your diamond appear larger and enhance its natural beauty.
-
Finger Size: The same diamond will look different on different hand sizes—consider trying on various carat weights to find your perfect fit.
Why Choose Lab Grown Diamonds?
Lab grown diamonds offer the same brilliance, durability, and beauty as natural diamonds at up to 70% savings. This means you can choose a larger carat weight or higher quality grade while staying within your budget. All our lab grown diamonds are certified—stones below 1 ct are SGL Certified, while diamonds 1 ct and above carry IGI Certification for your peace of mind.
Ready to find your perfect diamond? Browse our collection of certified lab grown diamonds in all shapes and sizes, or contact our diamond experts for personalized guidance.
