Strike Water Calculator

This calculator finds the temperature your infusion mash water needs to be -- the strike temperature -- so that after it absorbs heat from the grain, the resulting mash settles at your target rest temperature. It uses the widely cited home-brewing formula from John Palmer's How to Brew: Strike Temp = (0.2 / R) x (T2 - T1) + T2, where R is the water-to-grist ratio in quarts per pound, T2 is Target Mash Temperature, and T1 is Grain Temperature. The 0.2 factor is an empirically derived correction that accounts for the heat the grain itself absorbs during the mash-in, since the grain always starts cooler than the water and pulls the mixture's temperature down toward its own. Target Mash Temperature is what Strike Water Temperature responds to most directly and moves it in the same direction; colder Grain Temperature pushes the required strike temperature higher, since more of the water's heat gets absorbed cooling the grain down.

A thinner mash -- a higher Water-to-Grist Ratio -- needs a smaller temperature overshoot to hit the same target, since more water dilutes the grain's cooling effect. Grain Weight, notably, does not affect the required strike temperature at all -- it only changes Water Volume, since temperature is a ratio-driven calculation independent of the total batch size. The result is capped between 140°F and 212°F to stay within physically realistic bounds.