• Carat measures diamond weight, not size or quality.
• Table size and cut grade are equally important.
• A diamonds "fire" or "brilliance" comes from having the right proportions to capture and reflect light back out of the table.

Carat measure a diamond's weight, not its size. In fact, many diamond cutters are lured into cutting a diamond fat to maximize its weight and price. We at Karat recommend that in addition to carat weight, you should consider two other criteria: table size (distance in millimeters across the top) and cut grade (quality of its cut). A diamond’s "fire" comes from how it captures and returns light back through the top, which requires more than simple weight. The most brilliant diamonds give up carat weight to achieve optimal table size and cut grade proportions.

It is entirely possible to have a diamond of a lower carat weight, but higher cut grade that "faces up" or appears larger than a diamond with a larger carat weight but poorer cut grade. As noted in the section on cut grade, when a diamond is cut with the proper proportions, the maximum amount of reflected light (or fire) is returned back out through the top of the diamond. So that, when a diamond is well cut, the maximum light reflected out of the top makes it appear larger. In addition, much of the weight of a poorly cut diamond, for example, may be "hidden" in the fattened base of the diamond, making the diamond appear smaller than its carat weight would imply when viewed from above.

Diamonds Size Chart

The following chart displays how diamonds of different carat weight and shape will appear when viewed from the top. Please be advised that your diamond may vary from the printout in aspect ratio, table, and depth.

What Carat Weight Is Perfect For Me?

To select the best carat weight you should consider her tastes, the size of her finger, the size of your setting, and your budget.

• If it is important to you have a large carat weight and you're working within a budget we suggest that you consider a diamond with a good cut, SI1 in clarity and a color grade closer to I than D.
• Diamond prices increase significantly at the full- and half-carat weights due to the demand. Diamonds just below these weights can cost significantly less, and, because carat weight is distributed across the entirety of the diamond, small size differences between a 0.96 carat and 1.00 carat are almost imperceptible.
• You should note that the smaller her finger, the larger the diamond will appear. For example a 1.0 carat diamond solitaire looks much larger on a size 4 finger than a size 9.
• Not every design, mounting or setting will fit all diamond carats sizes or shapes. If you have already committed to a setting, check the diamond specifications closely or ask a Karat diamond consultant for assistance.

For even more help determining what size is best, get an idea of what she prefers. With discreet research you can get the perfect surprise without even raising her suspicions. For ideas and suggestions on how to choose the perfect engagement ring, please read Karat’s Engagement Ring Guide.