Sourdough hydration calculator
Calculate water and salt for sourdough, including the flour and water in your starter. See total hydration and print a recipe card.
Open toolA LITTLE MATH. A BETTER BAKE.
Good bread starts
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One recipe workflow for loaf weights, total hydration and the starter you need. Save a private draft and print your kitchen card.
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Sourdough recipe and starter build calculator
Plan loaf weights, total hydration and a starter feed together. Save a local recipe, print the ingredient card and keep a starter reserve.
Two 750 g pieces at 70% hydration and 2% salt need 872.09 g total flour, 610.47 g total water and 17.44 g salt. At 20% prefermented flour with 100% hydration starter, use 348.84 g ripe starter, add 697.67 g flour and 436.05 g water. For a 30 g reserve, build 378.84 g starter: a 1:2:2 feed uses 75.77 g seed, 151.53 g flour and 151.53 g water.
Try the worked example, or explore our baker’s percentage: flour, water and starter.
Made for a real task
The starter build includes a 30 g reserve; only 348.84 g goes into the dough. Quantity planning, not a fermentation forecast.
Read how this site works for the calculation approach, limitations and how to report a problem.