Professional Heart Diamond Size Chart & Conversion Tool

MM to CT / CT to MM Heart Shaped Diamond Size Comparison
0.18-5.20 cts (Excellent Cut)
HEART SHAPE CARAT WEIGHT HEART SHAPE MM SIZE (RATIO of 0.95 - 1.02) EXCELLENT CUT
0.18 - 0.21 ct.3.50 - 3.70 mm.
0.23 - 0.26 ct.3.80 - 4.10 mm.
0.27 - 0.29 ct.4.20 - 4.40 mm.
0.30 - 0.38 ct.4.50 - 4.70 mm.
0.40 - 0.45 ct.4.90 - 5.10 mm.
0.50 - 0.57 ct.5.20 - 5.50 mm.
0.60 - 0.65 ct.5.60 - 5.70 mm.
0.70 - 0.75 ct.5.80 - 6.10 mm.
0.80 - 0.85 ct.6.10 - 6.30 mm.
0.90 - 0.95 ct.6.20 - 6.50 mm.
1.00 - 1.10 ct.6.40 - 6.70 mm.
1.20 - 1.30 ct.7.00 - 7.40 mm.
1.50 - 1.60 ct.7.50 - 7.90 mm.
1.70 - 1.80 ct.8.00 - 8.20 mm.
2.00 - 2.20 ct.8.30 - 8.60 mm.
2.40 - 2.60 ct.8.40 - 8.90 mm.
2.70 - 2.85 ct.8.80 - 9.30 mm.
3.00 - 3.20 ct.9.30 - 9.80 mm.
3.40 - 3.60 ct.9.50 - 9.90 mm.
4.00 - 4.20 ct.9.80 - 10.00 mm.
4.40 - 4.60 ct.9.90 - 10.30mm.
5.00 - 5.20 ct.10.50 - 11.10 mm.
NGD Diamonds – Contact us for any specific size requirement

Heart Shape Diamond Size Chart (Very Good Cut)

0.17 - 2.20 cts (Very Good Cut)
HEART SHAPE CARAT WEIGHT HEART SHAPE MM SIZE (RATIO of 0.90 - 1.05) VERY GOOD CUT
0.17 - 0.21 ct.3.30 - 3.70 mm.
0.23 - 0.26 ct.3.60 - 3.90 mm.
0.27 - 0.29 ct.4.00 - 4.30 mm.
0.30 - 0.38 ct.4.20 - 4.60 mm.
0.40 - 0.45 ct.4.60 - 4.90 mm.
0.50 - 0.57 ct.4.90 - 5.30 mm.
0.60 - 0.65 ct.5.30 - 5.70 mm.
0.70 - 0.75 ct.5.50 - 5.80 mm.
0.80 - 0.85 ct.5.80 - 6.00 mm.
0.90 - 0.95 ct.5.90 - 6.30 mm.
1.00 - 1.10 ct.6.10 - 6.50 mm.
1.20 - 1.30 ct.6.60 - 7.00 mm.
1.50 - 1.60 ct.7.10 - 8.50 mm.
1.70 - 1.80 ct.5.00 - 5.30 mm.
2.00 - 2.20 ct.7.90 - 8.20 mm.
2.40 - 2.60 ct.8.00 - 8.50 mm.
2.70 - 2.85 ct.8.40 - 9.00 mm
3.00 - 3.20 ct.8.90 - 9.30 mm.
3.40 - 3.60 ct.9.00 - 9.40 mm.
4.00 - 4.20 ct.9.30 - 9.50 mm.
4.40 - 4.60 ct.9.40 - 9.80 mm.
5.00 - 5.20 ct.9.80 - 10.80 mm.

Ideal Proportions for Heart Shape Diamonds

ParameterExcellentVery GoodGood
Table (%)53% - 63%52% or 64% - 65%51% or 66% - 68%
Depth (%)58% - 62%56% - 57.9% or 62.1% - 66%53% - 55.9% or 66.1% - 71%
GirdleVery Thin to Slightly ThickVery Thin to ThickVery Thin to Thick
CuletNoneVery SmallSmall

What is the Recommended Length to Width Ratio in Heart Cut Diamonds?

Category Length to Width Ratio
Excellent 0.95 - 1.02
Very Good 0.89 - 0.94 or 1.03 - 1.05
Good 0.83 - 0.87 or 1.06 - 1.10