# Strike Water Calculator

Strike water temperature is the temperature at which mash water must be heated so that it settles to a target mash temperature after absorbing heat from dry grain. The calculation is strike temp = (0.3822 / R) × (target − grain temp) + target, where R is the water-to-grain ratio in liters per kilogram. A thinner mash needs a smaller overshoot.

Dry grain absorbs heat from the water. Strike water has to start hotter than the mash temperature you want, and how much hotter depends on the ratio.

HTML version: https://brewgravity.com/calculators/strike-water/

## Inputs

- **Grain weight (kg)** (min 0, step 0.1) — default: 5
- **Target mash temp (°C)** (step 0.5) — default: 66
- **Grain temperature (°C)** (step 0.5) — default: 20
- **Water-to-grain ratio (L/kg)** (min 0.5, step 0.1) — default: 3

## Outputs

- **strike**: Strike temp
- **strikeF**: Strike temp (°F)
- **water**: Strike water
- **absorb**: Lost to grain

## FAQ

### What water-to-grain ratio should I use?

Around 2.6–3.2 L/kg (1.25–1.5 quarts per pound) for a traditional mash. Brew-in-a-bag brewers often mash much thinner, at 4 L/kg or more, which needs a lower strike temperature because there is proportionally less grain to heat.

### My mash came in low. What now?

Add boiling water and stir, or apply direct heat if your tun allows it. Roughly 1 liter of boiling water per 20 liters of mash raises the temperature by about 2 °C. Overshooting is harder to fix, so approach from below.

### Does grain temperature really matter?

Yes, more than people expect. Grain stored in a cold garage at 5 °C rather than a 20 °C kitchen needs several degrees more on the strike water for the same target.

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Source: https://brewgravity.com — Free strike water calculator: strike temperature and volume for a single infusion mash from grain weight, grain temperature, target mash temperature and water-to-grain ratio, with a reference table and an explanation of mash temperature effects.