If your good with math and numbers, and know the starting tcc% of the extract/biomass, you can be nearly exact on the dosing mg.
Example
Say you have 1 gram of distillate, and (for easy math here) it's 100% tcc. If you make 10 edibles (same size aprox) will yield 100mg an edible (1000mg total before portioning).
If your distillate is 90%tcc, then you make 10 edibles (again the same aprox size), each edible will be 90mg.