Carat Weight Estimator
Estimate gemstone carat weight from dimensions and specific gravity for mounted and unmounted stones.
Inputs
mm
mm
mm
Results
Estimated Weight
3.09 ct
ShapeRound Brilliant
Weight0.62 g
Weight618.4 mg
Depth %66.7%
L:W Ratio1
How to Use This Calculator
- Select the gem Shape: round brilliant, oval, emerald cut, pear, or marquise.
- Enter the Length, Width, and Depth in millimeters using calipers or a gem gauge.
- Enter the Specific Gravity of the gem material (e.g., diamond = 3.52, ruby = 3.99).
- Review the Estimated Weight in carats — useful when a scale is unavailable.
- Use the result to cross-reference with price-per-carat tables for value estimation.
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