# 🍺 Top-Down Brew: Decoction Percentage

## Purpose: Calculate the percentage of mash to boil for a decoction mash

Current temperature
Next mash step temperature
Boiling temperature
Thermal loss factor

Results: *** Waiting for results ***

## Notes

This calculator estimates the percentage of the mash that needs to be boiled to reach the next temperature step in a decoction mash. The formula is from a Decoction mashing mini-FAQ by Marc de Jonge.

Either fahrenheit or celsius units can be used but be sure to keep the temperature units consistent for all of the inputs. Mixing fahrenheit and celsius values will produce errors. The default values are in fahrenheit.

The suggested thermal loss value is either 10C or 18F. This value may need to be adjusted up or down depending upon the heat loss from your equipment.