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Diamond Size on Finger: Breakdown and Chart

by Hunter Kemp
Last updated on October 18, 2023
Diamond Size

If you’re looking to buy an engagement ring, you’re likely paying attention to things like cut, clarity, setting, and style. But don’t forget to consider how big the diamond will look on your significant other’s finger! Even if you were to search “diamond size chart on finger,” though, it can be difficult to determine how any diamond will look on your partner’s. How large a diamond looks is an important piece of choosing the perfect diamond ring, and there are multiple factors that go into it. One such element is carat weight, which is perhaps the most important one. But it’s certainly not the only thing that determines how diamond size will be perceived. Diamond shape, for example, plays an important role as well.

Carat Weight

Before anything else, it’s important to clarify that “carat” is not the same as “karat”. The latter has to do with gold purity, not diamonds. Diamond carat is the weight of a diamond, with one carat being equal to 0.2 grams (or 200 milligrams). And while a higher carat diamond will be a larger diamond than a lower carat one, a 2 carat diamond won’t necessarily be twice the size of a 1 carat diamond. Additionally, two diamonds of the same carat weight may not look identical in size. Because diamonds are three-dimensional objects, they each have a width and length as well as a depth. You’ll only see the length and width from a top-down view, so a diamond with greater depth may not necessarily look bigger from that angle. However, the diamond’s depth (along with its other measurements) is important in determining how that diamond reflects light. In the next section, we’ll explain more about these other diamond measurements.

Diamond Size

While diamond size roughly corresponds with carat weight, the two values aren’t exactly the same. Actual diamond sizes– possibly even more so than carat weight– are one of the most important things to consider when assessing how big a diamond will appear on your engagement ring. A diamond’s size is usually described in millimeters (mm), and it refers to how large the diamond will look from a top-down view. As you can see in the chart below, different carat weights have different diamond sizes. These diamond sizes will also be different based on each diamond’s shape– the chart below is specifically for round diamonds.

Diamond Proportions

The proportions of a diamond will affect how large the stone appears as well as how much it sparkles. One of these measurements is the diamond’s length-to-width ratio. Each diamond shape has a narrow range of ideal length-to-width ratios that make for the best-looking stones. For instance, round diamonds and square diamonds will have ratios close to 1.0. Certain fancy shape diamonds, like ovals, will have slightly larger ones. These differences can affect how large the diamond looks, which we’ll discuss more in the section on diamond shape. If you want to look at a full list of the ideal ranges for length-to-width ratio for different diamond shapes, the International Gem Society has a guide here

Table Percentage

A diamond’s table percentage is another important measurement to consider. The table is the flat facet on top of the stone, which is the first surface that light hits when it enters a diamond. From there, the table refracts it and then reflects it onto the diamond’s many other facets. This is what makes a diamond sparkle, so the table certainly plays a critical role in the diamond’s brilliance. The table percentage of a diamond is the width of its table divided by its diameter. In order for a diamond to properly reflect light, its table percentage must be within a certain range. As is the case with the length-to-width ratio, this range will depend on the diamond’s shape. Staying within this will help you avoid a dull-looking diamond and make sure you have a radiant, eye-catching stone. While the brilliance of a diamond won’t necessarily make it look bigger, it can certainly draw more attention to it.

Depth Percentage

The depth percentage of a diamond is its depth divided by its diameter. While diamonds that are shallow– wider and not as deep– tend to look larger, they won’t reflect light as well and may appear darker. On the other hand, a diamond that is too deep will allow light to escape through the bottom. It’s important, then, to choose a diamond whose depth percentage is within the ideal range for its shape. This will maximize the sparkle and brilliance of the stone, making your engagement ring look truly stunning. For a full list of the ideal ranges for both depth percentage and table percentage for different diamond shapes, you can refer back to the same list from the IGS.

Diamond Shape

The diamond’s shape is another factor that can have a major impact on how large a center stone seems. Oval cut and emerald cut diamonds are two of the diamond shapes that appear the largest, followed closely by the pear cut and marquise cut. Most of these share attributes like a greater surface area, a larger table, an elongated shape, and a lower depth percentage. A round brilliant cut diamond or a princess diamond will tend to look smaller.

Diamond Cut

Sometimes confused with diamond shape, diamond cut refers to the actual cutting of a diamond’s facets. This determines how well light is refracted within the stone and reflected back out of it, which affects the diamond’s brilliance and sparkle. And while round brilliant cut diamonds don’t have the same enlarging effect that other shapes do, they have the potential to be exceptionally eye-catching for this reason. In fact, round brilliant cut diamonds are the only shape assigned cut grades. Their facets are precisely placed and sized in alignment with universally accepted standards, allowing the stone to achieve maximum sparkle. If you’re looking for a round brilliant cut diamond that has been cut with an unparalleled level of precision and symmetry, the Clean Origin Hearts and Arrows collection is a perfect choice. Only 1% of all diamonds earn this cut grade and display a breathtaking “hall of mirrors” effect.

Diamond Setting

With a halo setting, you can increase the overall carat weight of your diamond ring and create the appearance of a larger center stone without having to increase diamond size. Any side stones– especially a full halo– will make a smaller carat diamond look larger. You’ll also save money this way, too. A single diamond of a certain diamond carat size will cost more than multiple diamonds totaling the same diamond carat size. 

Thickness of Band

Though the diamond itself is of primary importance, it’s also essential to consider the rest of the engagement ring! The ring size, band width, and finger size of the wearer will all impact how large the diamond appears. Different diamond sizes could look larger or smaller in proportion to everything else around them. For the band, you want to make sure that you don’t choose one that is too big for the diamond. Smaller diamonds, such as a half carat diamond or even a quarter carat diamond, would look the best with a much thinner band. A thinner band will make any diamond size look bigger, but it’s especially important for a smaller diamond with a lower carat weight. A much larger, thicker band will make a diamond of the same carat weight look smaller and less prominent.

Finger Size

Choosing a diamond size that would look best with the size and shape of your finger is also important. Even if you were to search “diamond size chart on finger,” it might be difficult to get a sense of what different diamond sizes or diamond carat weights would look like on your finger. Selecting the right diamond size for your engagement ring can not only make the center stone look bigger, but it can also enhance the natural shape of your finger. For short or thick fingers, you might want to go for an elongated cut, such as an oval or emerald. This will make your fingers look longer. For long fingers, a round diamond can make them look shorter. Keep finger size in mind when choosing a band, too. A thicker band could look bulky on a small finger, but it could look appropriately sized on a larger finger. If the wearer of the ring is particularly self-conscious about their fingers, choosing a diamond size that will best complement their hands can give this person even more confidence when they wear their beautiful diamond ring.

Making Your Diamond Ring Look Best

If you’re looking to really make your diamond stand out, there are a variety of ways to do so. Diamond carat size is something to consider, but so are qualities like shape, depth percentage, band thickness, and the measurements that give the stone its actual diamond size. There’s truly so much that goes into creating a stunning ring. And with Clean Origin, you have endless options as far as maximizing your diamond’s appearance of size. 

Clean Origin provides you with the opportunity to build your own ring. This way, you can take each of these elements into account and create a ring that is everything you want it to be. You can browse some of our most popular styles for ideas or build a ring that is completely your own. And in addition to being of the highest quality, all the diamonds featured in our engagement rings are lab grown. This means they have ethical origins and come with a lower impact on the environment. Lab grown diamonds are easily the most responsible choice and they’re the best option financially, too. Lab grown diamonds are 20-40% less expensive than mined diamonds, due largely to their shorter supply chain. 

Looking for personalized assistance with choosing your ring? Schedule a virtual consultation with one of our jewelry experts or visit a Clean Origin showroom near you. We’re happy to help you find the perfect ring!