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March 8th 2022

The 2.5 Carat Diamond Engagement Ring Guide

By Devin Jones

2.5 carat diamond rings are impressive to behold, but if you’re not careful they can leave quite an impression on your wallet as well. Below are our top tips for getting the very best 2.5 carat diamond ring for your budget.

Did you know? The average price of a 2.5 carat diamond is over $40,000 as of July 2022.

How Big Is A 2.5 Carat Diamond Ring?

According to our diamond size chart, the average 2.5 carat round diamond is 8.71 mm wide (about 1/4 of an inch) with a surface area of 59 square millimeters and weighs half a gram. It might sounds small, but this is actually considered quite large by diamond standards (as you can see in our 2.5 carat diamond rings on hand section).

2.5 carat diamonds are considered big for an engagement ring since 2.5 carats is more than double the average carat weight of an engagement ring diamond in the US, which is currently 1 carat. In fact, according to a 2018 study conducted by Daily Mail the average diamond size that women consider “big” is 2.4 carats.

The Best Color Grades For 2.5 Carat Diamonds

According to StoneAlgo's internal data, the most popular 2.5 carat diamond color grades are G color (24%) and H color (20%). The chart below shows the popularity of all diamond color grades for 2.5 carat round diamonds on StoneAlgo.

2.5 Carat Diamond ring

Most Popular 2.5 Carat Diamond Color Grades

We typically say that the best color grades for a 2.5 carat diamonds are I color or H color because the diamond will look nice and white but you won't fall into the trap of overspending for quality you cannot appreciate with the naked eye (such as D color). For example, can you tell the difference between the colorless 2.5 carat D color diamond for $42,000 and the 2.5 carat I color diamond for $22,000 below?

2.5 carat I color diamond 2.5 carat D color diamond

Click the above images for more details & videos

However, even J color diamonds with faint or medium fluorescence can look crystal clear – especially once they’re set in an engagement ring setting. If you’re considering a yellow or rose gold engagement ring you could even go for a K color diamond since the darker setting color makes the diamond look relatively whiter than it normally would.

What do 2.5 carat diamonds look like with different color grades? Check out these images of 2.5 carat diamonds ranging from D colorK color. Click on a diamond for more details.

2.5 carat D color diamond 2.5 carat E color diamond 2.5 carat F color diamond 2.5 carat G color diamond 2.5 carat H color diamond 2.5 carat I color diamond 2.5 carat J color diamond 2.5 carat K color diamond

Click the above images for more details & videos

It’s difficult to see the differences between specific diamonds even when seen side-by-side in a grid like this one, and especially when viewed from above. However, if you view videos of the D color and K color diamonds next to each you can clearly tell the difference in a side view of the stones.

The difference in price is large though, ranging from about $65,000 for a 2.5 carat D color to $26,000 for a 2.5 carat K color, assuming VS1 clarity for both diamonds. Additionally, you can click on each of the images above to get the actual prices and more details on each specific diamond.

Given that round cut diamonds tend to hide color better than most fancy shapes, we generally recommend considering a higher (better) color grade for most fancy shapes than for round cut diamonds. How much better? Move up 1 color grade from what we recommend for round diamonds when shopping for a fancy shape. For example, if we recommend an H color for round diamonds, consider a G color for your fancy shape.

2.5 Carat Diamond Ring Price Chart

2.5 carat diamond ring prices vary significantly based on the shape, color, and clarity of the diamond you choose, as well as the metal and style of the engagement ring setting (solitaire, 3 stone, pave, halo, etc.). In this section we'll focus primarily on diamond prices, not setting prices.

There are many variables that affect diamond pricing, some of which you may be familiar with already (cut, symmetry, polish, and clarity grades for example) and some of which are more nuanced (the specific location and type of inclusions, specific dimensions of the diamond, etc.).

According to our diamond price calculator, the difference between 2.5 carat diamond prices and 2 carat diamond prices is about 44%. The difference between 3 carat diamond prices and 2.5 carat diamond prices is about 40%.

As if all that was not enough, the price of any specific diamond will change over time, and these changes can be significant.

Below you can see an example of our 2.5 carat diamond price chart for round diamonds. The average price for a 2.5 carat diamond is roughly $47,000 at the time of this writing (March 2022). To see the most up to date info check out our live updated 2.5 carat diamond prices page.

2.5 carat diamond prices

Learn more about 2.5 carat diamond prices on StoneAlgo

2.5 Carat Diamond Rings On Hand

One common concern amongst buyers is: what will the ring look like on her hand? Given that there are different hand sizes we have put together on-hand pictures for 2.5 carat weight diamonds on various ring/finger sizes.

2.5 carat diamond ring on size 4 finger

Above: 2.5 carat diamond ring on size 4 finger

2.5 carat diamond ring on size 5 finger

Above: 2.5 carat diamond ring on size 5 finger

2.5 carat diamond ring on size 6 finger

Above: 2.5 carat diamond ring on size 6 finger

2.5 carat diamond ring on size 7 finger

Above: 2.5 carat diamond ring on size 7 finger

2.5 carat diamond ring on size 8 finger

Above: 2.5 carat diamond ring on size 8 finger

2.5 Carat Diamond Ring Settings

Settings deserve a section of their own, as they can vary quite a bit and serve different purposes. The most popular engagement ring designs for 2.5 carat diamond rings are:

Let’s go over a few examples of what each looks like and what it means for the appearance of a 2.5 carat diamond.

2.5 Carat Solitaire Engagement Rings (Also Known As A Prong Setting)

If you love your stone and want avoid distractions, a solitaire setting is the setting to choose. A solitaire engagement ring setting puts all the emphasis on the center stone and you can still choose the number of prongs as well as additional band styles if you want personalize the setting a little bit more (more on bands further down).


You can expect to pay around $450 for a 18k yellow gold setting like this solitaire engagement ring setting from Blue Nile

2.5 Carat Halo Engagement Rings

Want to make the diamond look even bigger than it already is? The halo setting’s small diamonds surrounding the center stone create a visual effect that enlarges the appearance of the center stone.


When it comes for the surrounding stones clarity and cut do not matter quite as much as they do for the larger center stone, you only want to make sure you get a similar color grade to the center stone. A halo engagement ring in 18k white gold starts at about $1,390.

2.5 Carat Three Stone Engagement Rings (3 Stone Setting)

Another way of achieving this visual effect, yet to a lesser scale, is to have two sides stones of whatever shape you like. The Three Stone Setting is beautiful and becoming ever more popular.


A three stone engagement ring in 18k white gold starts at about $3,220.

2.5 Carat Pave Engagement Rings

As previously mentioned, customization of the band is yet another way of personalizing your ring. The most common style is the Pave, which consists of placing small diamonds across the band. You can have any setting matched with any band style.


In this example we are looking at a solitaire setting with a pave band. A 1/4 carat total weight pave engagement ring in 18k white gold starts at about $1,450 (like this one from Blue Nile).

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