Work out yeast pitching rate instantly with clear inputs, formula shown and shareable results.
Pitching rate is expressed as million cells per millilitre per degree Plato: 0.75 for ales, 1.5 for lagers and up to 2 for high-gravity worts. Total cells scale with volume and gravity, then divide by viability because dead cells contribute nothing. A standard 11 gram dry yeast packet supplies roughly 200 billion viable cells.
Pitching rate
Cells (billion) = rate x degrees Plato x volume (L)
Viability correction
Cells to pitch = cells required / viability %
A long lag phase, excessive ester and fusel alcohol production, stuck fermentation and greater risk of contamination taking hold. Under-pitching is the commonest fermentation fault.
Yes, though less often. Very high pitch rates suppress ester formation, give a thinner flavour profile, and can cause premature yeast autolysis and a rubbery off-flavour.