What does this tool do?
Hydration is the weight of water divided by the weight of flour, expressed as a percentage. A starter at 100% hydration contributes equal weights of flour and water, so including it keeps the calculation honest for sourdough bakers.
The Formula
Hydration % = total water ÷ total flour × 100; total flour includes half the starter weight at 100% hydrationFrequently Asked Questions
What hydration should I use for bread?
A beginner-friendly dough is often 65–75%. Sandwich bread sits around 60–70%, while open-crumb sourdough and pizza can go above 80%. Strong bread flour handles higher hydration better than soft flour.
Should I count the starter in the calculation?
Yes, for an accurate total. A 100% hydration starter is half flour and half water, so add half its weight to each side. Neglecting it makes the dough seem wetter than the stated hydration.