Whether you are using the three months’ salary ‘rule’ or simply looking for the biggest diamond within your budget, you may have wondered about the average diamond size for an engagement ring.

The size of an engagement ring is a deeply personal choice and has many influencing factors; while bigger is not always better, it is important that the diamond is of a size where it can be seen and admired.

If you have already started your diamond research, you will know that cut quality has the largest impact on the aesthetics of a diamond. Once you are familiar with cut quality, choosing a carat weight is the fun part!

The Magic Number

So, what is the magic number that is sure to have your intended saying “I do”? In short, the average engagement ring size in the U.S. is 1.00ct with the U.K. going slightly lower at 0.60ct.

A one-carat diamond has a tangible, rounded appeal. It has been glorified in film, music, and advertising as an impressive and desirable size for an engagement ring, with a huge percentage of buyers aspiring to this size.

You will notice that there can be a dramatic price increase between 0.822ct to 1.023ct diamonds.

If we use these Whiteflash diamonds as an example, that rise in price becomes clear. Both are AGS certified stones, with a color grading of H, a clarity grading of VS2, a cut grading of Ideal, and eye-clean. There is the 0.201ct difference between the two stones, yet there is a price difference of $3,205. You really do pay more for the ‘magic’ number.

You may have also noticed that there are less diamonds falling between 0.85ct and 0.99ct available on the market. A diamond purchase is driven by emotion and the demand for 1.00ct diamonds has resulted in cutters aiming for this as a goal post. Instead of cutting the diamond to a size that will deliver the best results, cutters know a full 1.00ct meets the buyer’s demand.

This drives home the importance of cut quality. Do not choose a 1.00ct diamond with a lower cut grade simply because it is 1.00ct. A poorly cut diamond will lack light handling properties which will affect brilliance and fire, and this will make the diamond appear smaller.

How ‘Big’ is the Average Engagement Ring?

A common misconception is that the carat weight directly indicates the size of the diamond. This is not true. While carat weights offer us a basic understanding of measurement (for example, we know a 1.00ct round brilliant will look bigger than a 0.50ct round brilliant), the surface area and ‘size’ of the diamond will vary greatly from cut to cut.

As this chart shows, two diamonds of the same carat weight can look very different sizes, with marquise and oval cuts offering the biggest impact for their carat weight.

Another factor which is so often overlooked by buyers is how big the diamond will actually appear on the hand.

A buyer may insist on a 3.00ct diamond for their engagement ring, only to find that it looks extremely large on their hand or is impractical for everyday wear. Similarly, a buyer may be looking at the lower end of the scale and a 0.15ct diamond and find that the stone is lost entirely either due to a badly chosen setting or the size being too small for the wearer’s hand.

Charts like the one above or online diamond size simulators will give you a clearer idea of how a diamond will look on your hand.

The Final Word

Does the average size really matter? In my opinion, the answer is no. An engagement ring should not be dictated by changing trends or societal pressures; it is a deeply personal purchase that should be led by your own tastes and requirements.

Buying online from vendors like Whiteflash, James Allen, and Blue Nile is the best way to get the most from your money, and it enables you to browse and truly compare the diamonds your shortlisted. Furthermore, you can avoid any additional pressures from salespeople, allowing you to find the perfect ring and spend an amount you are comfortable with.

The only rule when it comes to choosing a carat size for your engagement ring is combining it with the best possible cut quality and a good color and clarity grading. A diamond that ticks all these boxes is sure to turn heads, no matter what size it is.