Cooling and Evaporation Calculator

This page provides a calculator for estimating the rate of "natural" cooling (of wort or water) after boiling, without the use of cooling devices such as a counterflow or immersion chiller. This estimate may or may not be accurate enough for your purposes; at temperatures below 140°F to 160°F (60°C to 71°C), the estimate may be increasingly inaccurate. At temperatures below 120°F (50°C), the estimate is almost certainly wrong. The temperature estimates are based on the results of my blog post Predicting Wort Temperature After Flameout.

This page also provides a calculator for estimating the rate of evaporation at a specified sub-boiling temperature. (At boiling, the evaporation rate is a function of how much heat is being supplied.) This calculator assumes that the evaporating steam is not under pressure. The formula for evaporation is based on several measurements and some guesswork, and it may or may not be accurate enough for your needs.

Common Inputs:

Input Units: metric or U.S. customary (e.g. gallons, ounces)
Boiling Point of Water (°F):
Kettle or Pot Diameter (inches):	(surface area of liquid)
Opening Diameter (inches):	(often same as kettle/pot diameter)
Volume (G):

Cooling:

At time:	minutes after boiling, temperature ≈ 0.0°F
Formula:	temperature = A × exp(−B × time) + C

Evaporation:

At temperature:	°F, evaporation rate ≈ 0.0 G/hr