The Diamond Pro

What is CTTW for Diamonds?

By Michael Fried

Scared of getting ripped off? Don’t want to waste your money? Confused by all the choices? Contact us.
For a limited time, take advantage of James Allen’s 25% OFF Pre-Black Friday Sale!

If you’ve spent time looking at engagement rings and other diamond jewelry online, you may have noticed the acronym “CTTW” alongside other important details such as cut, clarity, color and carat weight. 

CTTW stands for “carat total weight,” or “total carat weight.” It’s a metric that’s used to measure the total weight of all of the diamonds in a specific piece of jewelry, such as a tennis bracelet or a pavé diamond ring. 

The carat weight of one diamond and the total carat weight of a diamond ring are very different numbers — a fact that can cause some confusion for first-time buyers. Below, we’ve explained how CTTW works, as well as how it differs from other measurements of a diamond’s weight.

CTTW vs. Carat: What’s the Difference?

As we covered in our guide to diamond carat weight, the carat weight of a diamond refers to the amount the diamond weighs, not its size. A diamond of a single metric carat weighs exactly 200 milligrams and can range in diameter from 5.60mm to 6.60mm depending on its cut grade. 

Carat weight is abbreviated at “ct.” When you’re viewing loose diamonds online, you’ll generally see their carat weight listed alongside factors such as cut, color and clarity. 

0.47cttw Double Halo from Blue Nile

CTTW, on the other hand, refers to the total weight of all of the diamonds in a specific piece of jewelry. Unlike ct., which is used to show the weight of a loose diamond or center stone, CTTW is only used to display the total carat weight of all diamonds. 

If you’ve read any of our other guides, you might have also seen the acronym “CTW” used to refer to total carat weight. Both CTTW and CTW are used worldwide and have the exact same meaning.

Many engagement rings only contain one center diamond. For example, this knife edge solitaire setting is designed to only hold a center stone. As a result, the ring’s total carat weight (CTTW) will be the same as the carat weight of the center stone.

Other rings, such as this lotus basket pavé engagement ring, have a band that’s lined with small diamonds. This specific ring features 36 small round diamonds, adding up to a total carat weight of 0.25 carat without a center stone. 

The total carat weight, or CTTW, of this ring is calculated by adding together the carat weight of the pavé set diamonds and the weight of the center stone. For example, by selecting this 1 carat round H VS2 diamond, the total weight of the setting and center stone is 1.25 carats. 

Some engagement ring settings can have a significant total carat weight even before the center stone is added. For example, this grande halo split shank setting has a 0.70 CTTW without any center stone due to its 64 pavé and halo set diamonds. 

Total Carat Weight (CTTW) and Diamond Prices

The price of a diamond increases exponentially with its carat weight. For example, a 0.50 carat round, H color, VS2 diamond like this one from Blue Nile sells for $1,243. A 1.00 carat diamond with the same specifications costs $5,453, despite only being twice the carat weight. 

The reason for this is simple. Large diamonds are significantly rarer than smaller diamonds and as a result, they can command higher prices on the market. Because of this, a large diamond is always going to be worth significantly more than a smaller diamond of the same quality.

1.15cttw Princess Cut Pave Engagement Ring

This isn’t the case with a ring’s total carat weight. Because this figure is made by adding up the carat weight of all of the ring’s small diamonds, there isn’t an exponential relationship between the ring’s total carat weight and its value.

For example, mounted in this solitaire setting, the 1.00 carat H color, VS2 diamond above costs $5,673 in total. This ring has a total carat weight of 1.00 carat. 

Meanwhile, this 0.5 CTTW pavé engagement ring with this 0.50 carat H color, VS2 diamond is available for $2,763. It also has a total carat weight of 1.00 carat. 

This means that if you’re on a limited budget, a pavé or halo setting with a fairly high total carat weight but a small center stone could be a good idea. While you won’t get the full wow factor of a large center stone, a ring of this type can look beautiful and elegant, all at a lower cost.

Other Factors to Look For in a Diamond

The carat weight of a diamond — or, in this case, the total carat weight of a ring — is only one of several factors you should consider when you’re choosing an engagement ring. 

Other factors, such as a diamond’s cut, color and clarity, also play a role in its appearance and value. Known as the 4 Cs, these factors all interact with each other to affect the way a diamond looks and the amount you’ll pay for it. 

We’ve covered these in more detail, as well as what you should look for, in our guide to buying a diamond

Conclusion

CTTW, or total carat weight, always refers to the total weight of all diamonds in a ring, bracelet, earrings or other pieces of jewelry. When you’re viewing a setting on its own, it’s the weight of the halo or pavé diamonds. For a complete ring, it’s the weight of all small diamonds and the center stone. 

Carat weight, which is abbreviated as ct, cw or CW, only refers to the weight of the center stone on its own.

While a ring with a large total carat weight can look impressive, it’s important to remember that the weight of the center stone is usually the biggest factor in determining an engagement ring’s value. 

Need help buying diamond jewelry? Contact our experts and we’ll help you choose the highest quality loose diamond, engagement ring, bracelet, pendant or earrings for your budget. 

About the author
Mike learned the diamond business from the ground-up at Leo Schachter Diamonds - one of the world's top diamond manufacturers. He has been recognized as a diamond industry expert by Time, PeopleMoney, The Daily Mirror, NerdWallet, The Times Herald, Yahoo Finance Australia, The Art of Charm, The Washington Diplomat, The Next Web, and more. See more
Top Recommended Vendors
James Allen James Allen is the leader in online diamond sales. Their imaging technology is at the point where it's almost the same as inspecting a diamond with a jeweler's loupe. Their customer experience is best in class, and they have recently upgraded their non-engagement jewelry inventory as well. And for a limited time, take advantage of their 25% Off pre-Black Friday Sale!
What we love about them:
  • No questions asked returns within 30 days of shipment. James Allen will send you a paid shipping label to return the ring.
  • Lifetime Warranty
  • Free International Shipping
  • Free prong tightening, repolishing, rhodium plating and cleaning every 6 months
  • Provide insurance appraisals
  • One free resizing within 60 days of purchase
  • Free ring inscriptions
  • Best-in-class high quality imagery of all diamonds in stock
  • 24/7 Customer Service
  • Best-in-class packaging

Blue Nile Blue Nile is the largest and most well known internet jewelry seller. They have the industry-leading largest available exclusive online inventory. Their high quality images are catching up to James Allens' and their prices are amazing.  
What we love about them:
  • No questions asked returns within 30 days of shipment. Blue Nile will send you a paid shipping label to return the ring.
  • Lifetime Warranty
  • Free Shipping
  • Free prong tightening, repolishing, rhodium plating and cleaning every 6 months
  • Provide insurance appraisal
  • One free resizing within the first year of purchase
  • High quality images of about half of their diamonds
  • 24/7 Customer Service
  • 100% credit towards future upgrades (must be at least double in value)
  • Best in class fulfillment

Still afraid of getting ripped off?

Before you buy a diamond, get personal buying advice from industry veterans. We'll help you get the best diamond for the money.

Ask your diamond purchase question here

  • This field is for validation purposes and should be left unchanged.

DISCLAIMER: We don't use your email for marketing. Period.

Why we are doing this for free?

Click for Diamond Purchase Advice 100% Free

Ask your diamond purchase question here

We are a team of diamond experts who will teach you to identify scams and avoid spending money on features you can't see. Tell us as much information as possible to help us help you (ie, budget, preferences, etc)

  • This field is for validation purposes and should be left unchanged.

Cancel

DISCLAIMER: We don't use your email for marketing. Period.

Please enter your email address to receive your personal code:

Here is your coupon code: GFDSF3GF