There are three calculators operated by filling in the blanks, but first you'll need to download a 'plug-in' to make them operate.

One calculator tells you how many yards of fabric of what width you'll need to produce binding of a certain width.

Another tells you how many squares of a given fabric depending on it's width.

The third tells how many half-square triangles you can get out of your fabric (Gudrun reports that this one didn't run on her Mac).

Check it out at: www.quiltpox.com/calculators.html