Sourdough Starter Feeding Calculator
Sourdough Starter Feeding Calculator
Get exact flour and water amounts for any feeding ratio — with temperature adjustment and a complete bake schedule builder.
Feeding Ratio Calculator
Enter your starter weight, pick a ratio, drag the temperature slider. We'll output exact gram amounts and a temp-adjusted peak time.
At 72°F — timing estimates are close to average.
Your Feeding Amounts
Bake Schedule Builder
Tell us when you want to bake. We'll work backwards and give you a complete feeding timeline.
Your Bake Schedule
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Use the float test — a spoonful of fed starter that floats in water at peak means it's ready.
Ready to start baking?The Mother is a 288-year-old heritage culture — pre-fed, active, and ready to bake on arrival. No building from scratch.
Get The Mother →More sourdough calculators:
Bulk Fermentation Timer Recipe Scaler Water Temp (DDT) Cups → Grams Starter Troubleshooter All Tools →Sourdough Starter Feeding Ratios — Complete Guide
A feeding ratio is written as starter : flour : water. The most common is 1:1:1 — one part each, by weight. If you have 50g of starter, add 50g flour and 50g water for 150g total. The ratio controls how fast your starter peaks. A 1:1:1 peaks in 4–5 hours at room temperature. A 1:10:10 won't peak for 16–24 hours.
Which Ratio Should You Use?
- 1:1:1 — Baking in 4–5 hours.
- 1:2:2 / 1:3:3 — Baking same day, levain built at lunch.
- 1:5:5 — The sweet spot for most home bakers. Feed at night, bake in the morning. The Mother's default.
- 1:10:10 — Infrequent bakers, once-daily feeding routine.
Temperature Changes Everything
At 65°F the same 1:5:5 feeding might not peak for 14–16 hours instead of 10–12. At 80°F it could peak in 7–8 hours. The calculator above adjusts for your kitchen — use it before committing to a bake schedule. Easiest hack: oven with just the light on reads 75–78°F, no equipment needed.
Timing estimates assume bread or all-purpose flour at the indicated temperature. Whole wheat and rye ferment faster. Use the float test as your final confirmation.