Sourdough Starter Feeding Calculator
Calculate flour and water needed for any sourdough starter feeding ratio. Maintain a healthy active starter for baking or storage.
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Sourdough Starter Feeding Guide
What is a Sourdough Starter?
A sourdough starter is a stable culture of wild yeasts and lactic acid bacteria living in a flour-water mixture. The wild yeasts (mainly Saccharomyces, Candida) produce CO₂ for bread rise. Lactobacilli produce lactic and acetic acids — the sour flavour and microbial protection. Active starter: doubles in volume within hours of feeding. Smells pleasantly sour, slightly fruity. Many small bubbles visible. Discard portion: the unfed starter portion removed before feeding. NOT waste — perfect for: discard recipes like pancakes, crackers, or flatbreads that use the flavour without needing the leavening power of an active starter.
What should I know about Feeding Ratios Explained?
Ratio format: starter:flour:water. 1:1:1 means equal parts of all three. Common ratios: 1:1:1 — high concentration of starter culture relative to fresh food. Peaks quickly (3-4 hours at 22°C). Needs feeding 2-3× daily if at room temp. Best for: quick activation before baking. 1:2:2 — moderate dilution. Peak 5-6 hours. Once daily feeding sufficient. Most home bakers' default ratio. 1:5:5 — significant dilution. Slower peak (8-12 hours). Suitable for cooler temperatures or once-daily feeding cycles, since the extra dilution slows fermentation down to match a less frequent feeding schedule.
What do I need to know about Building Toward a Bake?
Most recipes need a 'levain' or 'leaven' — a quantity of active starter ready to add to dough. Build with sufficient lead time: night before bake: 1:2:2 feed of small starter quantity (10g + 20g + 20g = 50g total). Morning of bake: this should be peaked and ready to use. Larger bake (multiple loaves): build in 2 stages. Day 1 evening: 20g + 40g + 40g (1:2:2). Day 2 morning: 50g + 100g + 100g. Use ~250g leaven that evening for two loaves. Hydration affects timing — 100% hydration, where water equals flour by weight, is the most common standard and gives predictable, well-documented timing for most recipes.
What's the key thing to understand about Storage and Troubleshooting?
Room temperature (18-25°C): feed once daily minimum. Twice daily if very active. Fridge storage: stable for 2-4 weeks unfed. Bring to room temp, feed 1:2:2 daily for 2-3 days before baking. Hooch (dark liquid on top): indicates starter is hungry. Stir in or pour off. Feed immediately. Floppy/no rise after feeding: starter weak — try 2-3 feeds at 1:2:2 daily. Increase frequency. Mould: rare but possible. Surface mould (pink, orange, fuzzy) — discard whole starter. Throughout the jar, uniform discolouration or fuzzy patches spreading beyond the surface mean the whole starter should be discarded and a new one started, rather than risking an unsafe bake.