Professional Oval Diamond Size Chart

Detailed Oval Cut Size Comparison From CT to MM / MM to CT by Gemologists
Oval Cut Diamond Conversion Tool From CT to MM / MM to CT
0.04 - 5.25 cts.
OVAL CUT CARAT WEIGHT OVAL CUT LENGTH MM SIZE OVAL CUT WIDTH MM SIZE
0.04 - 0.07 ct2.50 - 3.40 mm.2.00 - 2.40 mm.
0.08 - 0.12 ct3.40 - 4.80 mm.2.40 - 3.00 mm.
0.13 - 0.17 ct3.90 - 4.40 mm.2.80 -3.10 mm.
0.18 - 0.22 ct4.10 - 4.60 mm.3.00 - 3.40 mm.
0.23 - 0.28 ct4.50 - 5.10 mm.3.30 - 3.60 mm.
0.30 - 0.37 ct4.90 - 5.60 mm.3.60 - 4.00 mm.
0.40 - 0.48 ct5.60 - 6.00 mm.4.00 - 4.40 mm.
0.50 - 0.58 ct5.90 - 6.30 mm.4.40 - 4.60 mm.
0.60 - 0.69 ct6.30 - 6.70 mm.4.60 - 4.80 mm.
0.70 -0.78 ct6.60 - 6.80 mm.4.80 - 5.20 mm.
0.80 - 0.88 ct6.90 - 7.30 mm.5.10 - 5.40 mm.
0.90 - 0.98 ct7.20 - 7.80 mm.5.20 - 5.50 mm.
1.00 - 1.15 ct7.90 - 8.20 mm.5.50 - 5.80 mm.
1.20 - 1.27 ct8.10 -8.30 mm.6.00 - 6.10 mm.
1.30 - 1.45 ct8.40 - 8.50 mm.6.00 - 6.20 mm.
1.50 - 1.60 ct8.50 - 8.80 mm.6.20 -6.40 mm.
1.65 - 1.80 ct8.90 - 9.60 mm.6.60 - 6.80 mm.
2.00 - 2.30 ct9.80 - 10.10 mm.7.10 - 7.30 mm.
2.40 - 2.60 ct10.30 -10.70 mm.7.50 - 7.80 mm.
2.70 - 2.90 ct10.70 - 11.00 mm.7.80 - 7.90 mm.
3.00 - 3.30 ct10.90 - 11.60 mm.8.00 - 8.40mm.
3.40 - 3.60 ct11.50 - 12.00 mm.8.40 - 8.70 mm.
3.70 -3.90 ct12.00 - 12.35 mm.8.80 - 8.90 mm.
4.00 - 4.20 ct12.25 - 12.50 mm.8.80 - 9.00 mm.
4.40 - 4.70 ct12.40 - 13.00 mm.9.00 - 9.30 mm.
5.00 - 5.25 ct13.00 - 13.60 mm.9.40 - 9.70 mm.
NGD Diamonds – Contact us for any specific size requirement

Ideal Proportions for Oval Cut Diamonds

Oval Cut Diamond Recommended Proportions Guide
ParameterExcellentVery GoodGood
Table (%)67% - 72%59% - 66% or 73% - 75%59% - 66% or 73% - 75%
Depth (%)64%75%58% - 63.9% or 75.1% - 80%
GirdleVery Thin to Slightly ThickVery Thin to ThickVery Thin to Thick
CuletNoneVery SmallSmall

What is the Ideal Oval Cut Diamond Length to Width Ratio?

Category Length to Width Ratio
Excellent 1.00 - 1.03
Very Good 1.30 - 1.34 or 1.51 - 1.55
Good 1.25 - 1.29 or 1.56 - 1.60