Hey DrGodMan,
I'm afraid this answer is a little late, but you've probably already found an answer by now, haven't you?
So I'm assuming that you mean "calculate", right?
To do this, you first need to know what the total weight of a tablet will be -> test run with fillers only, and then weigh tablet
Now that you know how much a tablet will weigh, you can calculate it quite easily;
e.g.
- one tablet weighs a total of 350mg
- you want ~50mg active ingredient per tablet
-> per 50mg you need 300mg filler
- let's say you have 100g of active ingredient that you want to press into tablets
- so you should get about 2,000 pieces (100g / 0.05g)
- 2000 x 0.3g = 600g filler
Of course, it is important that you mix everything thoroughly for a long time to minimise the difference/fluctuation in the active ingredients of the individual tablets.
Hope this helps you. Or maybe the next person who asks this question XD