Mathematical justification is here

Dilute Calculator:

Initial Alcohol Strength. %ABV
Initial Alcohol Volume, ml
Desired Alcohol Strength. %ABV
Add Water, ml.






Fortify Calculator:

Initial Alcohol Strength. %ABV
Initial Alcohol Volume, ml
Fortify Alcohol Strength, %ABV
Desired Alcohol Strength. %ABV
Add Fortifier, ml.






Mix Calculator:

First reagent strength. %ABV
First reagent Volume, ml
Second Reagent Strength, %ABV
Second reagent Volume, ml
Final Alcohol Strength. %ABV
Final Volume. ml