Add water as an ingredient. The calculator scales your recipe. It does NOT add the water your ice normally contributes during shaking / stirring. For a spirit-forward batch (Old Fashioned, Manhattan, Negroni family), add ~20-25% water to the batch volume to replace the stirring dilution you'd normally get. For a shaken-cocktail batch, add ~25-30% water. Skip this step and the batch reads hot and unstructured.

Freezer-door spec. A batch that lives in a freezer bottle needs even more dilution built in (25-30% for stirred, 30-35% for shaken) because it's poured directly over ice at service without further shaking. It comes out of the freezer at ~-15°C, near-instant chill on the ice, minimal further dilution during pour. This is the classic "freezer Martini" trick.

Add citrus fresh. Lime and lemon juice oxidize fast — 30% loss of titratable acidity within 8 hours, ~50% by 24. Pre-batching a Margarita or Daiquiri with the citrus already in it means service starts already off-balance. Batch everything EXCEPT the citrus; add the citrus at service, or portion single-service citrus doses into ice-molds you drop in on order.

Omit carbonation, always. Sparkling wine, tonic, ginger beer, soda — never in the pre-batch. They go in the individual serving glass at pour time. A batch of pre-mixed Aperol Spritz is flat by the third glass.

Shelf life by ingredient class. Spirit-and-fortified-wine batches (Manhattans, Negronis): 1-2 weeks refrigerated. Batches containing juice: use within 24 hours, ideally same shift. Batches with dairy or cream: same shift only, and shake before every pour. When in doubt, taste before serving.