Sourdough Starter & Feeding Calculator

Sourdough Starter Guide

Understanding Feeding Ratios

The feeding ratio (starter:flour:water) controls fermentation speed. A 1:1:1 ratio (equal parts) peaks in 4-6 hours at room temperature — suitable for same-day baking. A 1:2:2 ratio takes 6-8 hours. A 1:5:5 ratio is used for an overnight counter fermentation or a cold-retarded 12-hour proof. A 1:10:10 ratio produces very gradual fermentation over 24+ hours. Choose the ratio based on your baking schedule — you want to use the starter at peak activity (domed top, full of bubbles, just before it st

Starter Hydration

Starter hydration is expressed as a percentage of water to flour by weight. 100% hydration (equal weight flour and water) produces a thick batter — most common for beginners, easy to assess activity by volume. 125% hydration: slightly more liquid, more active, slight tang. 75% hydration: stiffer, longer fermentation, milder flavour — used for Italian lievito madre. Higher hydration starters ferment more quickly and show more activity. Lower hydration starters are more stable for long storage and

Reading Your Starter

Signs of a healthy, active starter at peak: doubled or more in size (mark the container with tape before feeding). Domed top — not yet fallen back down. Interior is full of bubbles, webby, honeycomb structure. Smells pleasantly sour and yeasty — like yogurt or mild beer. Floats when a small amount is dropped into water (the float test — not infallible but indicative of active fermentation). Signs of an unhealthy starter: liquid layer on top (hooch — starter has run out of food, stir it in or pou

Discard Uses

Sourdough discard is unfed starter that would otherwise be thrown away — it has weaker leavening power than active starter but retains all the flavour. Discard uses: sourdough pancakes (tangy and light), waffles, flatbreads, pizza dough, crackers, banana bread. Discard can be stored in the fridge for up to a week and added to recipes for flavour without leavening. Adding discard to yeasted recipes gives sourdough flavour with reliable rise from commercial yeast. Never waste discard — it develops