The top dropdown offers four options for calculation. Two for calculating the first grain addition and two for calculating further grain additions. The two for calculating the first grain addition are of course also suitable for recipes with only one grain addition.

• For the first grain addition, Simple calculation:
  This calculation uses the same formula that calculators from other sites use. This formula generalizes a few complex relationships. We have also produced a formula ourselves using similar generalizations, but it only differed slightly from this formula.
• For the first grain addition, Detailed calculation:
  There are a few additional input fields to choose from here. For example, if a substance has a heat capacity of 1.5 kj/kg K, then it takes 1.5 kj to heat 1kg of it by 1°C, or it releases 1.5 kj when it cools by 1°C. The moisture content of grain has a noticeable effect on the heat capacity of the grain, simply because water has a much higher heat capacity than completely dry grain. Moistures of 10-15% are normal for unmalted grain, 5% for fresh malt. The higher the moisture of the grain, the higher its heat capacity, the more the temperature of the grain influences the temperature of the mash. The heat capacity of completely dry grain depends primarily on the oil content of the grain, as oil has a very high heat capacity. The value of 1,194 kj/kg K suggested here is realistic for grains such as wheat, rye and barley at 20°C. Corn probably has a slightly higher heat capacity. Heat capacities are also temperature-dependent. Both that of water and that of grain. So it does not take the same amount of energy to heat the same mass of water from 10 to 20°C as it does to heat it from 20 to 30°C. This calculation takes this into account for both the water and the grain.
  If you play around a bit with the values in the additional fields, you will realize that it doesn't make much difference. In other words, the calculation using the conventional formula is sufficient.
• For further additions of grain: Calculation of the required mash temperature:
  This calculation is intended for recipes in which the mash is cooled or heated after an initial grain addition and rest in order to bring it to a certain temperature for the next grain addition and rest. The calculator assumes a heat capacity of 1,194 kj/kg K (at 20°C and 0% moisture) and 10% moisture of the grain.
• For further additions of grain: Calculation of additional water:
  This is about recipes in which the mash temperature is to be adjusted by adding water during the second addition of grain and rest. Either the required water temperature is calculated for a desired amount of water or the required amount of water is calculated for a desired water temperature.

Losses due to lack of insulation and evaporation are not taken into account. This reduces the reliability of the calculation results in practice. The calculator is therefore no substitute for practical experience.