Or the way you all want to use it is wrong. As I've said in other threads, you will make more accurate gear without powder calc, without knowing anything about the compound all together (it is helpful to know the purity in % of your powder...).
I'll quote myself from other threads:
Originally Posted by UA_Iron
If you're homebrewing you dont even need the powder calculator (which most of you use wrong anyway).
Mix your shit in a graduated cylinder. I'll explain.
Say you want to make 50ml of Test E with 2% BA, 20%BB (though you dont need any BB for test E):
50ml*.02 = 1ml BA
50ml*.20 = 10ml BB
12.5g Test E
Start by putting your BB into the graduated cylinder up to the 10ml mark, then put 1ml BA into that. It's easier in this order because it's easier to find the 10ml mark than the 1ml mark on most graduated cylinders.
Now dump your powder into that. Some will probably stick to the walls etc, swish it around to capture that. It's typically easier to use a wider graduated cylinder for this operation because its makes it easier to put stuff into it.
Let that sit and the test E powder dissolve completely.
Once dissolved, pour oil into the cylinder until you hit the 50ml mark.
You now have accurately dosed Test E without even measuring the volume of oil - now filter and put into your sterile media however you desire.
*I suggest making 5-10ml more than what you want to yield because there will be losses in each step.
The powder calc is a volumetric equation; it accounts for the volumes of what you want to use. If you're guessing numbers for things - or using numbers based off some info from a forum somewhere along the lines of "I typically use .8 for eq, yields me good results" then there's no point in even buying a scale with a resolution of .01g or better to weigh out your powders - you're splitting hairs on one-step of the process and guessing on the next step.