🍺Home Brew Fermentation Timer

Beverage type, fermentation temp & gravity → estimated primary and secondary time

How to Use the Home Brew Fermentation Timer

Fermentation time depends heavily on yeast type, temperature, and sugar content. Select your beverage type, fermentation temperature range, and original gravity to get an estimated primary and secondary fermentation timeline. These are estimates — always confirm completion with a hydrometer. Two identical FG readings taken two days apart is the gold standard for fermentation complete.

Typical Fermentation Times by Style (at 68°F / 20°C)

BeveragePrimarySecondary
Ale7–14 days5–10 days
Lager14–28 days14–28 days cold
Wine10–21 days10–21 days
Hard Cider7–14 days5–10 days

Frequently Asked Questions

The airlock stopped bubbling — is it done?

Not necessarily. CO₂ production can stop before all sugars are fermented, especially in warm conditions. Always confirm with two consecutive identical hydrometer readings.

Does temperature fluctuation hurt fermentation?

Yes — rapid swings stress the yeast and can produce off-flavors (fusel alcohols, acetaldehyde). Keep fermentation in a stable-temperature environment: a basement, cooler, or fermentation chamber.