How big is a 1.5 carat oval diamond?

By HeyGema™ · Updated

In short

A 1.5 carat oval diamond measures about 9.2 x 6.3 mm. It faces up 6% bigger than a round diamond of the same weight. On a size 6 finger it covers 38% of the width. For the same weight, a round diamond is 7.4 mm.

Carat to mm calculator

About 9.2 x 6.3 mm

An estimate for a well-cut stone. A deep or shallow cut faces up smaller or bigger.

1.5 ct oval
9.2 x 6.3 mm
1.5 ct round
7.4 mm
Side by side
1.5 ct round inside 1.5 ct oval
A 1.5 carat oval diamond beside a 1.5 carat round, to the same scale.

1.5 carat oval diamond size

A well-cut 1.5 carat oval diamond measures about 9.2 x 6.3 mm (0.36 x 0.25 inches) at a length-to-width ratio of 1.45:1. It faces up 6% bigger than a round diamond of the same weight. It weighs 0.30 grams.

1.5 carat oval size by length-to-width ratio

The same weight can be long and narrow or short and wide. These are 1.5 carat sizes at each ratio. A longer ratio runs the stone along the finger and makes it look slimmer. The face-up area stays almost the same.

1.25:1
Length x width: 8.5 x 6.8 mm
Width on the finger: 41% of a size 6 finger
1.35:1
Length x width: 8.8 x 6.5 mm
Width on the finger: 40% of a size 6 finger
1.45:1
Length x width: 9.2 x 6.3 mm
Width on the finger: 38% of a size 6 finger
1.55:1
Length x width: 9.5 x 6.1 mm
Width on the finger: 37% of a size 6 finger

1.5 carat oval on a finger

6.3 mm
6.3 mm stone on a 16.5 mm finger: it covers 38% of the widthA 1.5 carat oval diamond on a size 6 finger.
4
Finger width: 14.9 mm
Oval covers: 42%
5
Finger width: 15.7 mm
Oval covers: 40%
6
Finger width: 16.5 mm
Oval covers: 38%
7
Finger width: 17.3 mm
Oval covers: 36%
8
Finger width: 18.1 mm
Oval covers: 35%
9
Finger width: 18.9 mm
Oval covers: 33%

Oval sizes near 1.5 carat

1 carat
Length x width: 8.0 x 5.5 mm
Round of the same weight: 6.5 mm
1.25 carat
Length x width: 8.6 x 5.9 mm
Round of the same weight: 6.9 mm
1.5 (this page)
Length x width: 9.2 x 6.3 mm
Round of the same weight: 7.4 mm
1.75 carat
Length x width: 9.6 x 6.6 mm
Round of the same weight: 7.8 mm
2 carat
Length x width: 10.1 x 6.9 mm
Round of the same weight: 8.1 mm

1.5 carat in other shapes

Every row is a well-cut diamond of 1.5 carat. The last column is the face-up size against the oval.

Round
Length x width: 7.4 mm
Against oval: -5%
Cushion
Length x width: 6.4 x 6.4 mm
Against oval: -19%
Princess
Length x width: 6.3 x 6.3 mm
Against oval: -13%
Emerald cut
Length x width: 8.0 x 5.7 mm
Against oval: -2%
Asscher
Length x width: 6.3 x 6.3 mm
Against oval: -20%
Radiant
Length x width: 7.4 x 5.7 mm
Against oval: -8%
Pear
Length x width: 9.7 x 6.3 mm
Against oval: -8%
Marquise
Length x width: 11.9 x 6.0 mm
Against oval: +9%
Heart
Length x width: 7.4 x 7.4 mm
Against oval: -22%
Trillion
Length x width: 8.0 x 8.0 mm
Against oval: -18%
Baguette
Length x width: 9.2 x 4.6 mm
Against oval: -7%

Questions

A 1.5 carat oval diamond is about 9.2 x 6.3 mm at the usual 1.45:1 ratio.
Yes. Face-up, a 1.5 carat oval is 6% bigger than a 1.5 carat round (7.4 mm).
There is no rule. The stone is 42% of the width of a size 4 finger and 35% of a size 8. Compare it with a ring you have tried on in the finger chart above.
Yes. A lab grown diamond has the same density as a mined one, so it measures the same for the same weight.

More size charts