Hydration

Hydration is baker's shorthand for how much water is in a dough relative to flour, calculated by dividing water weight by flour weight and multiplying by one hundred. A dough made with 750 grams of water to 1000 grams of flour is 75 percent hydration. Sourdough recipes typically range from around 65 percent for easier-to-handle loaves to 85 percent or higher for very open, custardy crumb.

Hydration matters because it changes almost everything about how a dough behaves: wetter doughs ferment a little faster, spread more if under-proofed, and tend to produce a more open, irregular crumb, while stiffer doughs are easier to shape and hold their form better in the oven. Flour type also affects how much water it can absorb, so the same percentage can feel very different between a soft all-purpose flour and a strong bread flour or one with more whole grain.

A digital scale that measures in grams is the most important tool for tracking hydration accurately, since cup measurements vary too much to be reliable. A common mistake for beginners is jumping straight to a very high hydration dough before they can read fermentation and handle sticky dough, which usually ends in a flat, hard-to-shape loaf. Raising hydration gradually as your shaping skills improve is a more reliable way to work toward an open crumb.