The visual graphic of the Crown Angle Calculator gives you a view of the table and crown angle. If the angles are out of whack it will be more readily apparent than it might be just by seeing the numbers.

Example: Average Diameter: 6.55
Crown Height (MM): 0.85
Table Percentage: 62
Crown Height %: 12.98
Crown Angle (Degrees): 34.33

The above example will automatically round to 34.50 degrees when entered into the Cut Grader.

With this calculator you can figure the crown angle of a diamond with three pieces of information. You need to know the table percentage, the average diameter, and the crown height in millimeters. All of these should be measured, not estimated.  The hardest part (at least at first) is measuring the crown height.  Taking a front view of the diamond, use your table gauge to measure the crown at 4 crown bezel facets (skipping every other bezel facet).  Measure in the middle of the bezel facet, starting at the point of the kite shape.  Measure straight up (at 90 degrees to the girdle) to the table. Average the readings and use this number for the Crown Height field. Unless your diamond is larger than about 1.25 carats, your figure for the crown height in millimeters is usually under 1 mm. After you've measured the height, take an accurate measurement of the table (using the LONGEST table measurement), and the average diameter.  Enter your data into the Crown Angle Calculator.  After entering all three fields the crown angle will appear.

Using the Crown Angle Calulator with the Diamond Cut Graders:

You can open the Crown Angle Calculator when you are using any of the Diamond Cut Graders (except for the Princess/Emerald/Radiant cuts. These use Crown Height % rather than Crown Angles). Press the F7 key when you are on the Crown Angle field  and the Crown Angle Calculator will open. Enter the crown height in millimeters (the other fields have been filled in for you) and press Close or Escape.  The crown angle will be rounded to the nearest half degree.

Other options: You can change the data entry for Table from percentage to millimeters and the Crown Height from millimeters to percentage. Your choice. Simply highlight the field label as in the picture below and double-click.