What are Carats? A Guide to Carats in Engagement Rings & Engagement Ring Carat Comparison

A Guide To Understanding Engagement Ring Carats

You’ve decided it’s time to take the next step in your relationship and started to snoop around for the perfect engagement ring to propose with. Or, you know the question is coming and want to give hints about the engagement ring you believe symbolizes your love. Whether you’re a bride or groom or shopping just-because, understanding what to look for in an engagement ring is essential. While the setting and metal matter - the diamond carat weight may be the ultimate deciding factor. 

Carat, abbreviated as ct, is a unit of measurement specifically used for gemstones including diamonds. You will often see it referred to as both "carat weight" or "carat size." In the context of engagement rings, understanding carat weight is essential for making an informed decision about the overall look and feel of the ring as well as its value. By the end of this guide, the hope is that you walk away with the tools you need to evaluate carat sizes and quality better so that you can find the engagement ring that you love. 

What are carats? 

Carats are a unit of weight for gemstones, and one carat is equivalent to 200 milligrams. The term “carat” derives from the carob seeds. Because of their uniform size, these seeds historically were used as counterweights on balance scales to measure precious stones. Over time, the carat became the standard unit for weighing gemstones, providing a universal measurement for comparing their sizes. 


Emerald Cut Diamonds Ranging in Carat Size on Hand

Does size matter? 

Whether you’re going the modest route like Michelle Obama’s first one-carat engagement ring or you’re after a ring as extravagant as Elizabeth Taylor’s 33-carat engagement ring - size will play a role in your decision. However, it's important to understand that carats alone don’t determine the size or visual impact of a diamond. The overall appearance and sparkle of an engagement ring is influenced by a combination of factors, including cut, color, and clarity. Therefore, two diamonds with the same carat weight may appear different in size or brilliance due to variations in these characteristics. 

Carat, Cut, Color, and Clarity - All About The 4 C’s

As you embark on your journey of engagement ring shopping, you’re sure to come across the term “Four Cs,” which refers to carat weight, cut, color, and clarity. Each of these factors contributes to the overall quality and appearance of a diamond. While carat weight is a measure of the gemstone’s size, cut refers to the quality and symmetry of the diamond’s facets, color grades the presence of any warmth in the diamond, and clarity assesses the presence of any internal flaws or external blemishes.  

How To: Evaluating and Comparing Carat Size

If you keep these aspects in mind, you’re well on your way to finding the right carat size for you:

  1. Visual Size: While carat weight provides a numerical measurement, the visual size of a diamond is also influenced by its shape and cut. For example, a well-cut diamond will appear larger than a poorly cut one, even if they have the same carat weight. Instead, look at a diamond’s dimensions. A well-cut stone will maximize the millimeter width of the diamond making it appear larger with the same weight.
  2. Ratio: Elongated stones will have an extra identifier called a ratio. This dimension reflects the length of the stone in millimeters divided by the width. The number tells you whether your stone is cut longer or wider. The closer the number is to 2, the more elongated the cut, while a ratio closer to 1 gives it a shorter, wider, more square appearance. Most of the time, the longer the stone, the larger it will look. However, your favorite ratio should be based on personal preference for the style that suits you best.

    Radiant Cut Diamonds with Different Ratios on Hand

  3. Finger Size: The size of the bride’s finger can impact how a diamond appears. A one-carat diamond will look more substantial on a smaller finger, while the same diamond may seem modest on a larger finger. It may be helpful to try on rings with different carat sizes before making your final choice. (Have you checked out our Find Your Diamond Kit?)

    2.50ct Oval Cut Diamonds on Different Finger Sizes

  4. Budget Considerations: The bigger the diamond, the odds are that it’s more expensive. Carat weight significantly affects the cost of an engagement ring. As carat weight increases, the price tends to rise exponentially due to the relative rarity of larger diamonds. It’s essential to find a balance between size and budget to choose a ring that meets both criteria. 
  5. Carat Increments: Carat weights are often used in increments, and slight differences in carat weight may not be visibility noticeable. For example, a .90-carat diamond may appear very similar to a 1.00-carat diamond, but the price difference can be significant. 

    Asscher Cut Diamonds on Hand

Popular Carat Sizes To Consider

One way to come to a final decision is to be aware of what other people gravitate towards when it comes to carat sizes. Here’s an overview of the most popular sizes:

.50-1.00 Carats: Ideal for those who prefer a more delicate look. Despite a more modest appearance, smaller diamonds still pack lots of beauty and sparkle. This is one of the most popular ranges for those seeking a balance between size and budget. 

1.00-2.00 Carats: This range offers a statement without reaching the ultra-expensive side of an engagement ring budget. It’s perfect for those looking for more sparkle for everyday wear. 

2.00-3.00 Carats: This is the most popular range for lab diamonds. With lab diamond's excellent quality and price, this range has risen in popularity over the smaller stones we saw a generation ago. 

3.00 Carats and above: If you’re going for a luxurious statement that commands attention, this is the range for you. It’s sure to turn heads everywhere you go. 

Radiant Cut Diamonds on Hand


Finding an engagement ring is a deeply personal and memorable experience. It involves a delicate balance between personal preferences, budget considerations, and the unique qualities that symbolize your love story. As you navigate through the plethora of options, exploring various styles, cuts, and carat sizes, remember that the ideal ring is the one that resonates with both partners. Whether it’s a classic solitaire, a vintage-inspired design, or a contemporary masterpiece- the perfect ring, or in this case, carat size, is a reflection of your commitment and a timeless symbol of the love you share. Enjoy the process, savor the moments, and choose a carat size that speaks to your heart. 

With that said, you can be more confident in the decisions you make by educating yourself. Once you better understand what carats are and the impact they make on your choice, you’re one step closer to finding your dream ring. One sure way to do that is to keep the Four C’s (carat weight, cut, color, and clarity) in mind when exploring engagement ring options. The nuances between all of those important factors are how you find that delicate balance between your preferences, budget, and celebrating your love story. 

Need more help finding the right carat size? You can use our Diamond Engagement Ring Try-On Kit to help you explore the options available to you.

Shop Our Feed