Depending on the strength of rectification, the vapor temperature at the highest point of the still is lower and the alcohol content of the distillate is higher than calculated here. However, the direct correlation of vapor temperature at the highest point and the alcohol content of the distillate remains invariant. For example, 91°C (at the highest point of the still and at normal pressure) always means about 59%abv in the distillate. And also the correlation of alcohol content in the still and boiling temperature is always the same. For example, 12%abv always boils at about 91°C. Also, the temperature of the vapor directly above the boiler contents is always the same as the temperature in the boiler. Rectification causes the vapor temperature at the highest point to be lower than in the boiler and the alcohol content at the highest point to be higher than directly above the boiler contents.
It is possible to switch between percentage alcohol by volume, by weight and by mole (abv%, abw% and abm%).
The consideration of the air pressure has a significant influence on the result. If nothing is entered, the calculator assumes the local atmospheric pressure 1013.25 hPa.
Since almost no one has an absolutely accurate thermometer, an additional "thermometer error" can be specified. This can be determined with the help of the calculator Thermometer Error. Temperatures entered or calculated here are then those displayed on this thermometer, not the real ones.

Information about our boiling point data and the influence of atmospheric pressure