How big is a 1 Carat Diamond ?

It is very important to choose a perfect diamond with size and shape. For every woman, her engagement ring is the most important piece of a jewellery as it symbolize love and commitment. A diamond’s price can be determined by shape, colour, clarity and carat.

It is very true that the majority of people choose a 1 carat diamond for engagement rings. Why? It is because, No one can go wrong with a 1ct diamond for any shape or size they choose. It is necessary to know that diamond’s prices increase ascendingly and not linearly. This means that the price of a 2 carat diamond will not be twice the price of a 1 carat. It will be much higher.

The bigger the diamond, the higher the price difference. Depending on the quality, a 6 carat diamond can cost 20 times more than a 1 carat.

“How much is a 1 carat diamond?” The size of a 1 carat diamond is approximately 6.5mm. Well, the size of a 0.5 carat diamond is approximately 5mm. Even though the carat weight is 50% of a 1 carat diamond, it doesn’t look twice the small of a 1 caratt diamond.

While choosing a diamond of any shape it is important to keep in mind that a given increase in diameter will yield a larger increase in surface (crown) area and overall perceived size.


The length and width of a diamond will only tell you exactly how large the diamond will appear from above.

The carat weight and the same shape of two diamonds still may appear different because of their cut proportions. A deep cut would have smaller diameter than an ideal cut diamond due to its greater depth proportion. These differences are usually small, but can be noticed. A well cut diamond may even have a slightly lower carat weight than a deeply cut diamond, yet still have a larger diameter. Hence, making it appear larger in size.

The image will show you the difference between the two.

How Diamond Shape Affects Price

The shape of a diamond directly influences its price. Round diamonds are the most popular shape and higher in price as compared to other fancy shapes because of market demand, increased manufacturing costs, and their incredible brilliance.Fancy shaped diamonds include all diamonds including princess, emerald, asscher, cushion, marquise, radiant, oval, pear, and heart.

Choosing a fancy shaped diamond can save you more than 25% in price compared to a round diamond of similar size and quality. Fancy shapes such as marquise, oval, and pear are elongated and tend to appear larger than a round diamond. The most popular fancy shapes being princess, cushion, and radiant.

Two diamonds of equal carat weight may also appear very different in size based on the shape of the diamond. For instance, a 1 carat marquise tends to appear larger than a 1 carat round. The chart below illustrates why. For each diamond, the chart shows the following:

1CT Diamond Size