Trillion Cut Diamond Size Chart

On this page, you'll find our trillion cut diamond size chart that shows the actual size of each diamond, from 0.25 carat to 10 carat, in millimeters. This is a great way to compare the size of each diamond, and to see how the size of the diamond changes as the carat weight increases.

If you have been searching to find out what a 7mm trillion cut diamond should weigh, for example, you can use this simple chart to quickly convert from carat to MM and from MM to carat.

We cover all carat sizes from melee diamonds up to large 10 carat diamonds. To keep the trillion diamond size chart simple, we have only included carats in 0.25 increments, but if you have a specific carat size you want to check, you can use the search box below the chart to find it.

Also, you can click on any diamond in the chart to see detailed information on the proportions, and compare it to the ideal proportions for the specific trillion cut diamond.

Size Chart

0.25ct
4.87 x 4.87mm

0.50ct
6.14 x 6.14mm

0.75ct
7.03 x 7.03mm

1ct
7.74 x 7.74mm

1.25ct
8.33 x 8.33mm

1.50ct
8.86 x 8.86mm

1.75ct
9.32 x 9.32mm

2ct
9.75 x 9.75mm

2.25ct
10.14 x 10.14mm

2.50ct
10.5 x 10.5mm

2.75ct
10.84 x 10.84mm

3ct
11.16 x 11.16mm

3.25ct
11.46 x 11.46mm

3.50ct
11.75 x 11.75mm

3.75ct
12.02 x 12.02mm

4ct
12.28 x 12.28mm

4.25ct
12.53 x 12.53mm

4.50ct
12.77 x 12.77mm

4.75ct
13 x 13mm

5ct
13.23 x 13.23mm

5.25ct
13.45 x 13.45mm

5.50ct
13.66 x 13.66mm

5.75ct
13.86 x 13.86mm

6ct
14.06 x 14.06mm

6.25ct
14.25 x 14.25mm

6.50ct
14.44 x 14.44mm

6.75ct
14.62 x 14.62mm

7ct
14.8 x 14.8mm

7.25ct
14.97 x 14.97mm

7.50ct
15.14 x 15.14mm

7.75ct
15.31 x 15.31mm

8ct
15.47 x 15.47mm

8.25ct
15.63 x 15.63mm

8.50ct
15.79 x 15.79mm

8.75ct
15.94 x 15.94mm

9ct
16.09 x 16.09mm

9.25ct
16.24 x 16.24mm

9.50ct
16.38 x 16.38mm

9.75ct
16.53 x 16.53mm

10ct
16.67 x 16.67mm

Compare Trillion Cut to Other Diamond Shapes

We can also compare the trillion cut diamond size chart to other diamond shapes. The chart below shows the size of a 1 carat diamond in each shape, and how the face up area of each diamond compares to the trillion cut diamond.

The chart is sorted by the percentage difference between the average face up area of the trillion cut diamond and the average face up area of the other diamond shapes. The trillion cut diamond is shown in blue, with the other shapes behind them in grey.

We've also changed positive percentages to green, and negative percentages to red, to make it easier to see which shapes are larger, and which are smaller, than the trillion cut diamond.

For a more detailed comparison of trillion cut diamonds to other diamond shapes, you can click the links in the chart.

Trillion Diamond Buyer's Guide

If you want to make sure you are purchasing the best trillion diamond for your money, then you can consider the following criteria, so you can know what to look for and what to avoid when buying a diamond.

Color

The choice of ring will determine which color of trillion diamond will look best in it. The color of a diamond is graded on a scale of D to Z. The full scale is:

• D-F - Colorless
• G-J - Near Colorless
• K-M - Faint Yellow
• N-R - Very Light Yellow
• S-Z - Light Yellow

For a platinum or white gold solitaire ring, go with H, or if you prefer a yellow gold solitaire ring, choose J.

Clarity

The clarity of a diamond refers to the number and size of inclusions in the diamond. Inclusions are tiny flaws that are present in all diamonds, and they are what give each diamond it's unique character.

The clarity grading will tell you how many inclusions are present in the diamond, and how visible they are to the naked eye.

Graded by the GIA, the clarity scale is as follows:

• Flawless (FL). No inclusions or blemishes are visible under 10x magnification.
• Internally Flawless (IF). No inclusions are visible under 10x magnification, but blemishes may be visible.
• Very, Very Slightly Included (VVS1 and VVS2). Inclusions are difficult for a skilled grader to see under 10x magnification.
• Very Slightly Included (VS1 and VS2). Inclusions are clearly visible under 10x magnification, but can only be seen with effort.
• Slightly Included (SI1 and SI2). Inclusions are clearly visible under 10x magnification.
• Included (I1, I2, and I3). Inclusions are obvious under 10x magnification.

Our recommendation for trillion diamonds is to choose a diamond with a SI2 clarity grade or higher.

Buying Shy

A very common technique used when buying a diamond is to buy a diamond just shy of a full or half carat. For example, if you are looking for a 1 carat diamond, you might buy a 0.9 or 0.95 carat diamond instead. If you're looking at a 1.5 carat stone, then maybe look to buy shy and consider 1.4ct instead.

The price of diamonds jump at full- and half-carat weights, so buying shy can save you a lot of money and the difference in size is barely noticeable if you stick within 3-7% of the target carat weight.

Pro tip! We recommend that you buy a trillion diamond that is just shy of a full or half carat to save money.

Cut Parameters

To help you make a better decision on the cut of your diamond, you can use the parameters below to figure out whether a particular trillion diamond is worth considering.

• Depth: 32% to 80%
• Table: 50% to 70%
• Polish/Symmetry: Good or better
• Length-to-Width Ratio: 1 to 1.1

Diamond Certification

The gold standard for professional and unbiased diamond characteristic assessments is the Gemological Institute of America (GIA). The GIA is the world's foremost authority on diamonds and gemstones, and they are the most trusted source for diamond grading reports.

Another well-trusted diamond grading lab is the American Gem Society (AGS). The AGS is a non-profit organization that was founded in 1934, and they are dedicated to educating consumers about diamonds and gemstones.

Now, a certificate is not 100% reliable, but is still essential to have when considering a purchase of any diamond. Put simply, if a diamond is not certified by GIA or AGS, then it is almost guaranteed to be a lower quality diamond.

We recommend that you only consider diamonds that are certified by the GIA or AGS to ensure you get a high-quality stone.

Eye Clean

The term "eye clean" refers to a diamond that has no visible inclusions under 10x magnification. In other words, the diamond is completely free of inclusions that can be seen with the naked eye.

If you are able to see inclusions with the naked eye, then the diamond is not eye clean and you should not consider it for purchase unless you know what you are doing.

We recommend that you only consider diamonds that are eye clean to ensure you get a high-quality stone.

Photos

A lot of diamond purchasing is now done online, and this means you get access to a lot more stones than you would if you were shopping in a brick-and-mortar store. However, this also means that you have to rely on photos to make your decision.

Always review high quality photos, videos, or 360° views of the diamond you are considering. If the photos are not high quality, then you should not consider the diamond.

Red Flags to Consider

We've covered a lot of information about what to look for in trillion diamonds, but there are also some red flags that you should be aware of when buying a diamond. Make sure to consider the list below when evaluating a diamond to make sure you get the quality you are paying for.

Summary

Hopefully this trillion diamond size chart and buying guide has helped you to understand how to compare trillion diamonds to other shapes, how to convert their size from carat to MM and from MM to carat, and how the carat weight changes the physical size of the diamond.