Lallemand Dry Yeast Pitch Calculator
Estimate how many grams (and packets) of dry brewing yeast you should pitch based on batch size, gravity, and fermentation type.
How this Lallemand calculator works
This tool estimates yeast pitch requirements for dry brewing yeast in a practical, homebrew-friendly way. It starts with a standard pitch-rate model used by brewers: cells needed are based on batch volume, wort strength (in degrees Plato), and fermentation style (ale vs lager).
Once the required cell count is calculated, the tool converts that into grams of dry yeast using your assumptions for viable cells per gram and overall viability.
Core equation used
- Required Cells (million) = Pitch Rate × Volume (mL) × °Plato
- Required Cells (billion) = Required Cells (million) ÷ 1000
- Effective Cells per Gram (billion) = Cells per Gram × Viability
- Yeast Grams Needed = Required Cells (billion) ÷ Effective Cells per Gram
Why pitch rate matters
Pitch too little and yeast can struggle, producing off-flavors, stalled fermentation, or poor attenuation. Pitch too much and you may get a cleaner but less expressive profile than intended. The right target depends on beer style, gravity, and fermentation temperature.
- Ales: typically lower pitch rates than lagers.
- Lagers: generally need more cells for clean performance at cooler temperatures.
- High gravity beers: benefit from increased pitch rates due to higher osmotic stress.
Input guide for accurate results
1) Batch size
Enter your actual fermenter volume, not just kettle target. If you routinely lose wort to trub or transfers, account for that.
2) Original gravity
Use measured OG whenever possible. The calculator converts SG to Plato internally, because pitch formulas are built around Plato.
3) Fermentation type
Select the category that best matches your process. If you ferment warm lager strains or cold ale strains, consider choosing the middle "hybrid" option and adjusting with safety margin.
4) Cells per gram and viability
Dry yeast products vary by strain, production lot, and age. If your packet provides guaranteed cell count or viability information, use those values for better precision.
Practical example
Suppose you are brewing 20 L of 1.050 ale with 11 g packets, estimating 20 billion cells per gram and 95% viability. The calculator will estimate total grams needed, add your safety margin, and then convert to packet count.
In many standard-strength ales, this often lands around one packet, while stronger beers or lagers often require two or more.
Tips for better fermentation outcomes
- Rehydrate dry yeast according to manufacturer instructions for best viability.
- Control fermentation temperature from day one.
- Oxygenate higher-gravity worts properly.
- Use healthy nutrient practices if brewing very high-gravity beer.
- Record your fermentation results and adjust assumptions next batch.
Important note
This calculator is an educational planning tool, not a substitute for specific technical sheets from Lallemand or your yeast supplier. Always prioritize strain-specific recommendations when available.