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Strike water calculator

Enter your grain weight, water-to-grain ratio, grain temperature and target mash temperature. The calculator gives the strike temperature and water volume, and how much boiling water a step infusion needs.

Hands checking mash temperature with a digital thermometer in a large pot of grain
Photo: Markus Braun, Public domain, via Wikimedia Commons
Units
Step infusion (optional)
Strike water temperature—
Strike water volume—
Infusion water to add—
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How it’s calculated

  1. Strike: Tw = (0.2 / r) × (T2 − T1) + T2 (r = qt per lb, °F); metric Tw = (0.41 / r) × (T2 − T1) + T2 (r = L per kg, °C)
  2. Infusion: Wa = (T2 − T1) × (0.2·G + Wm) / (Tw − T2) (G = lb grain, Wm = qt already in the mash)

Assumptions

  • Assumes a preheated mash tun. All-in-one systems that heat the water to mash temperature first can skip the strike offset (toggle).
  • Thermal losses of your own tun are not modeled; note your real result in the brew log.

Worked example: 1.5 qt/lb, grain at 65°F, target 152°F → strike at about 163.6°F. Raising 10 lb from 152 to 168°F with 212°F water (15 qt in the mash) needs about 6.2 qt.

Sources: John Palmer, How to Brew: Initial infusion equation; Brewer's Friend docs: strike water; Craft Beer & Brewing: strike water tool

For guidance only: verify with your own readings, your equipment’s manual and the product labels.

All-in-one systems

Most electric all-in-ones heat the water to mash temperature and hold it with a controller, so the strike offset does not apply. Tick the all-in-one box, then follow your system's manual for when to add grain.

Questions

What water-to-grain ratio should I use?
1.25–2 qt per lb is common; BIAB and all-in-ones often run thinner mashes. Use the ratio your system's manual suggests.
Why did my mash land low?
Unheated tuns absorb heat. Note the miss in your brew log and adjust next time; the equation assumes a preheated tun.

Sources

  1. John Palmer, How to Brew