Diamond Grading Chart


Buying a diamond can be a very important and stressful decision, so it is important that you know as much as possible about the factors that determine the value of diamonds so that you can sleep well once you make your purchase.  Whether you are buying a ring with the diamond already mounted or trying to sort through hundreds or even thousands of loose diamonds to find the right one, evaluating the value of the diamond is a very important step that requires a lot of research. We have put together our Diamond Grading Chart to help compare the approximate prices for different diamond clarity and diamond color grades. This website was made to pull all of the most important information into one easy-to-find place.


(click chart to enlarge)

The above Diamond Grading Chart compares the prices of diamonds of different color and clarity grades. This chart is for a 1 carat (.97 carats – 1.03 carats) Round diamonds with “Very Good” cuts. It would be practically impossible to build a chart for all shapes/sizes/cuts, so we tried to build a chart with a very popular shape and cut to serve as a good point of comparison. We will be working on new charts in the future to provide you with even more information!

As mentioned before, sometimes you can buy jewelry or a ring with the diamond already mounted. While it is also important to evaluate the value of the included diamond in this situation, most of the content of this website is written for someone trying to sort through all of the loose diamonds for sale to find the perfect one.

Before getting into the process of selecting the right diamond, it is important to understand the main factors that affect the value (and price) of loose diamonds, known as the 4 C’s – Cut, Clarity, Color, and Carat Weight. Here are some brief descriptions of the 4 C’s, with links to pages with more in-depth information:

  • Cut - The cut of a diamond is largely considered the most important of the 4 C’s, and has to do with the proportions of a diamond, not the shape (i.e. Round, Princess, Emerald, Cushion, etc.). A diamond that is cut to perfect proportions will reflect the most light possible back to person looking at the diamond, which gives a diamond “brilliance” or “fire” (check out the graphic below that shows what happens to light for different types of cuts). Essentially, a well cut diamond will sparkle more than one that is not cut as well. Different companies and grading labs use slightly different scales, but in general diamonds can be rated Ideal, Excellent, Very Good, Good, Fair, or Poor.

cut light reflection4

  •  Clarity – When diamonds are forming in the Earth, internal flaws (called “inclusions”) can form within them. The diamond clarity grade gives you an idea of the number, size, and visibility of these inclusions. A more clear diamond will look better and will reflect more light than a less clear diamond (although the clarity will not affect this as much as the cut). Diamonds are graded on a scale from “Flawless” (F) to “Included” (I1, I2, I3) with many levels in between, although most online sellers and jewelers will not offer diamonds below the “Slightly Included” (SI1-SI2) grade. Click here for more information on diamond clarity grades.
  • Color – The color of a diamond refers to the “yellowness” of the diamond. White, or “colorless”, diamonds are more rare and often more desirable because they allow more light to pass through than diamonds that are lower on the color grading scale. The diamond color scale starts at “D”, which is considered colorless (along with “E” and “F”). As you move down the color scale, “G”, “H”, “I”, and “J” are considered to be near colorless, but start to show a very slight yellowish tint. Click here for more information on diamond color grades.
  • Carat Weight – The carat weight is simply the unit of measure for the weight of a diamond.


Each of the 4 C’s affects the value of loose diamonds in a different way, as you can see from the Diamond Grading Chart above. Because the 4 C’s all impact the price differently, you will have to make trade-offs based on your budget. After determining your budget, the next step is to determine how important each of the 4 C’s are to you and the person you are buying the diamond for. The best way to do this is to go look at different diamonds so that you can compare them side by side. Even if you plan on buying a diamond online, actually going to a jeweler and looking at diamonds of different cuts, clarity, colors, and carat weights is invaluable. Once you have an idea of the acceptable cut, clarity, and color grades of the diamond you want to buy, you can determine the size of the diamond that meets those criteria and your budget.

We hope that the information we provide, especially the Diamond Grading Chart, will help you with your decision!