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# Carat Weight Calculator

How to use this carat weight calculator for diamondsCarat-to-gram conversionOther similar toolsFAQs

If you need to know the weight of a specific diamond size, this carat weight calculator will greatly help. Whether you're a jewelry enthusiast, a diamond dealer, or simply curious about the value of your precious stones, calculating the carat weight of your diamonds is essential.

• The tool uses the dimensions of the diamond in mm to calculate the carat weight for that piece of jewelry.
• If you need to perform carat-to-gram conversions, go directly to the diamond weight and input it in carats to obtain it in grams. You don't need to input anything else.

## How to use this carat weight calculator for diamonds

To go from the dimensions of a diamond in mm to its carat weight, the calculator needs two pieces of information:

1. The diamond shape, which will determine the formula used.
• Most people will need to select the round shape, which comprises about 75% of all diamonds sold.
• Nevertheless, other shapes are getting increasingly popular recently, as they are usually less expensive.
2. The diamond dimensions:
• For round diamonds, you'll need to input the diameter and depth;
• For other diamond shapes, you'll need to input the length, width, and depth.

#### Optional values

1. Girdle thickness (optional): For more accuracy, we can consider the thickness of the girdle of the diamond using a scale of thin, medium, thick, super thick, etc.

• 0% - 1% Very thin or thin girdles;
• 1% - 3% if medium;
• 3% - 6% for thick and very thick girdles; and
• >6% for extra thick.

(the numbers above are the girdle percentage of the average diameter)

2. Correction factor: For non-circular diamonds, we can even add other . These factors range from -5% to 18%, depending on the diamond's shape and its geometrical irregularities.

🙋 Do you need to know the math behind this tool? Look at the formulas in our diamond weight calculator.

## Carat-to-gram conversion

One carat equals 0.2 grams. Therefore, to convert from carats to grams, you must multiply the weight in carats by 0.2. For example:

• 2 carats equal 0.4 grams because:
• 2 carats = (2 × 0.2) grams = 0.4 grams.
• 3 carats equal 0.6 grams because:
• 3 carats = (3 × 0.2) grams = 0.6 grams.
• 24 carats equal 48 grams because:
• 24 carats = (24 × 0.2) grams = 4.8 grams.

## Other similar tools

Discover more about diamond calculation with these tools:

FAQs

### What is the weight in carat of a 1.5 mm diamond?

A 1.5 mm round diamond will weigh about 0.015 carats for a 1 mm depth. For other diamond diameters or depths, use our carat weight calculator.

### What is the weight in carat of a 9x7 mm diamond?

The weight in carats of a 9×7 mm oval diamond will be between 2 and 2.5 carats, for depths between 5 and 6 mm. The exact answer will depend on the diamond depth, girdle thickness, and geometric irregularities.