Sourdough Calculator
Build a sourdough recipe from total flour, hydration and starter percentage, with the starter's flour and water counted.
About the Sourdough Calculator
Baker's percentages express each ingredient as a share of total flour. A 100%-hydration starter is half flour and half water, so it contributes to both totals; this calculator subtracts them so your dough's true hydration is what you set. Typical doughs are 65–80% hydration with 10–25% starter and 2% salt. Higher hydration gives a more open crumb but is harder to shape.
The formula
Starter flour = starter ÷ (1 + starter hydration); water to add = flour × hydration − starter water
Worked example
Example: Dough weight = 1,018 g
- Inputs: Total flour (incl. flour in starter): 550 g; Hydration: 83%; Starter (levain): 22 % of total flour; Starter hydration: 110%; Salt: 2%; Number of loaves: 1.
- Formula: Starter flour = starter ÷ (1 + starter hydration); water to add = flour × hydration − starter water
- Result: Dough weight = 1,018 g
Questions people ask
What does 75% hydration mean?
75 g water for every 100 g flour, including what's in the starter.
How much starter?
20% is common; less slows the rise, useful in warm kitchens.