Sourdough Hydration Calculator

Dough hydration

Sourdough hydration is water as a percentage of flour weight — the baker’s-percentage habit that makes dough feel predictable across batch sizes. This calculator scales flour, water and starter from a target hydration and loaf size so sticky high-hydration boules and tighter sandwich loaves are intentional. Remember that starter brings both flour and water; if you add 100 g of 100% hydration starter, you have already added 50 g flour and 50 g water toward the total. Salt is usually about 2% of total flour. Related dough tools: pizza dough and recipe scaling. Flour protein and wholegrain content change how a given hydration feels in the hands. Not food-safety advice for commercial production. Weigh in grams; cups fight hydration maths. Keep notes of bulk time and dough temperature beside the hydration figure so ‘72%’ means the same thing next month.

Worked example

For 500 g total flour at 72% hydration you want 0.72 × 500 = 360 g water before starter adjustments. If you use 100 g starter at 100% hydration, that contributes 50 g flour and 50 g water, so autolyse water might be 310 g against 450 g remaining flour — match the method you follow. Salt at 2% of total flour is 10 g.

Limits and assumptions

Flour absorbency varies by brand and season. Preferment builds need their own water accounting. Not a fermentation schedule.

Frequently asked questions

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