Starter Feeding Ratio Calculator

What the ratio means

A feeding ratio is written starter : flour : water, by weight. Feeding at 1:2:2 means that for every gram of starter you keep, you add two grams of flour and two of water — so 20 g of starter gets 40 g of flour and 40 g of water, making 100 g. All the ratios here keep the starter at 100% hydration; only the amount of fresh food changes.

Choosing a ratio

The ratio is really a timer. A small feed like 1:1:1 gives the culture little fresh food, so it peaks fast — typically four to six hours — and turns sour quickly afterwards. Bigger feeds dilute the culture and take longer to peak: 1:2:2 lands around six to eight hours, 1:5:5 around eight to twelve, and 1:10:10 can hold overnight and beyond. Pick the ratio that makes your starter peak when you actually need it, rather than fighting your schedule.

Reading the peak

A ripe starter has domed or just begun to flatten, smells pleasantly tangy rather than harsh, and is full of bubbles through the body of the culture, not just on top. Temperature moves everything: at 26 °C a 1:5:5 feed can behave like a 1:2:2 at 20 °C. If your kitchen runs cold, use a smaller ratio or find a warmer spot; if your starter races past its peak before you wake up, feed it more heavily.

Whatever ratio you settle on, consistency beats cleverness — the same feed at the same times teaches you exactly what “ready” looks like for your jar.