Sourdough Starter Feeding Ratio Calculator
Calculate the correct amounts of starter, flour, and water for any sourdough feeding ratio.
Works for 1:1:1, 1:2:2, 1:5:5, and any custom ratio.
What Is a Feeding Ratio? A sourdough starter feeding ratio is expressed as Starter : Flour : Water. A 1:1:1 ratio means equal parts by weight — 50g starter, 50g flour, 50g water. A 1:2:2 ratio means double the flour and water — 50g starter, 100g flour, 100g water.
How Ratio Affects Fermentation Higher flour ratios (1:5:5, 1:10:10) mean more food for the yeast — the starter rises more slowly, peaks later, and can be left longer before it overferments. This is useful if you bake infrequently or want to refrigerate between feedings. Lower ratios (1:1:1) peak faster — within 4-8 hours at room temperature.
Hydration The ratio of water to flour determines the starter hydration. 1:1:1 with equal flour and water = 100% hydration (same weight water as flour). You can vary the water to make a stiffer or wetter starter. Stiff starters (65-70% hydration) are less sour; wet starters (100-125%) are more active.
Levain vs Starter A levain (or pre-ferment) is a portion of starter fed specifically for a recipe. Build the exact amount you need for the recipe rather than feeding your whole jar each time. This way your main starter stays small and manageable.