Sourdough Hydration Calculator
Calculate dough hydration percentage from flour and water weights.
Results
Hydration percentage is the ratio of water to flour by weight - the single most important number in bread baking. At 65% hydration you get a stiff dough good for sandwich bread. At 75% you get a standard sourdough with moderate open crumb. At 80%+ you get the big holes of ciabatta. This calculator accounts for the flour and water contribution of your sourdough starter.
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Frequently asked questions
Start at 65-70% hydration. This gives a manageable dough that is easy to shape. As you gain experience, work up to 75-80% for more open crumb and better flavor.
A 100% hydration starter (equal parts flour and water by weight) is most common. If your starter is 50% hydration (stiffer), it contributes more flour and less water, lowering overall dough hydration.
78-85% hydration with strong bread flour produces the most open crumb. Ciabatta is typically 80-85%. Higher hydration requires better shaping technique and stronger flour.
Hydration controls dough texture, crumb structure, crust crispness and fermentation rate. Higher hydration = more steam = crispier crust and more open crumb, but the dough is harder to handle.
A 100g starter at 100% hydration contributes 50g flour and 50g water. Add these to your recipe's flour and water totals, then divide total water by total flour × 100.