Enter the grain weight, grain retention, water ratio, and strike volume into the calculator to determine the mash volume.

Mash Volume Formula

The following formula is used to calculate the mash volume for brewing beer.

MV = (GW * (GR + WR)) + SV


  • MV is the Mash Volume (gallons) GW is the Grain Weight (pounds) GR is the Grain Retention (gallons per pound) WR is the Water Ratio (gallons per pound) SV is the Strike Volume (gallons)

To calculate the mash volume, multiply the grain weight by the sum of the grain retention and the water ratio. Then, add the strike volume to the result. This will give you the total volume of mash needed for brewing.

What is a Mash Volume?

Mash volume refers to the total amount of water and grains combined in the mashing process during beer brewing. This volume is crucial as it affects the concentration of the sugars extracted from the grains, which in turn influences the alcohol content and flavor of the beer. The ideal mash volume varies depending on the type of beer being brewed and the specific recipe used.

How to Calculate Mash Volume?

The following steps outline how to calculate the Mash Volume using the given formula:

  1. First, determine the Grain Weight (GW) in pounds.
  2. Next, determine the Grain Retention (GR) in gallons per pound.
  3. Next, determine the Water Ratio (WR) in gallons per pound.
  4. Next, determine the Strike Volume (SV) in gallons.
  5. Finally, calculate the Mash Volume (MV) using the formula: MV = (GW * (GR + WR)) + SV.

Example Problem:

Use the following variables as an example problem to test your knowledge:

Grain Weight (GW) = 10 pounds

Grain Retention (GR) = 0.5 gallons per pound

Water Ratio (WR) = 1.5 gallons per pound

Strike Volume (SV) = 5 gallons