Yeast Cell Count Calculator

This yeast pitch calculator developed by Inland Island Yeast Laboratories will allow you to determine both the mass and volume of slurry that is needed for repitching to your next batch of beer.
  • First, enter your fermentation volume in units of standard U.S. Barrels (31 gallons) followed by your desired wort gravity in the yellow boxes on the left hand side of the calculator.
  • Next, take a representative sample of your slurry to be pitched and preform a hemocytometer cell count. Enter the results from your cell count in the yellow boxes at the bottom of the calculator.
  • Once all these data are entered, the blue cells will calculate the needed mass and volume of slurry to be pitched based on the inputs you provided.
If you have any questions, please feel free to contact us for further direction.  
Yellow Cells are Inputs
Blue Cells are Calculated
Fermentation Volume (BBL) This is the size of the equipment being used based on the standard US BBL = 31 Gallons Cell Count (Cells/mL) Fermentation Volume (gal) Fermentation Volume (mL) Desired Cell Concentration (Cells/mL-°P) Desired Cell Concentration (Cells/mL) Total # Cells for Pitch
Desired Gravity (°P) This is the expected gravity of the beer being pitched into Volume of Slurry Needed (mL) Volume of Slurry Needed (L) Volume of Slurry Needed (gal) Mass of slurry Needed (g) Mass of slurry Needed (Kg) Mass of slurry Needed (lb)
Desired Cell Concentration (Cells/mL x 1E6) This is the desired concentration of cells/mL based on beer style, wort gravity and yeast health
Density of Slurry (g/mL) This is the density of the slurry being pitched. This can be measured or if unknown go with 1.1 g/mL Total Cells Counted # of Squares Counted Dilution Live Cells Counted Dead Cells Counted % Viability (Do Not Pitch Under 90% Viability)