This calculator calculates for the amounts of stock chemicals to use to adjust the composition of a batch with three active ingredients. The initial weight of batch for adjustment to use is calculated given the final weight of batch. The amount of diluent (commonly water) to use is also calculated if needed to lower the concentration of a ingredient or component. Ideally, the purer a stock chemical used for active ingredient concentration adjustment is the better. This calculator can handle general cases where all three components (plus diluent) can be present in a stock chemical.