Hydration is the ratio of water to flour in your dough, expressed as a percentage. It's the single biggest factor that determines your bread's texture, crumb structure, and how the dough handles.
Hydration % = (Water Weight ÷ Flour Weight) × 100
500g flour + 350g water
350 ÷ 500 = 0.70 × 100 = 70%
500g flour + 400g water
400 ÷ 500 = 0.80 × 100 = 80%
Your sourdough starter is typically 100% hydration (equal parts flour and water). When calculating total dough hydration, include the flour and water from your starter in the totals. For example, 100g of 100% hydration starter adds 50g flour and 50g water to your recipe.
Dense, tight crumb. Firm dough.
Common uses: Bagels, pretzels, pasta, some rye breads
Low hydration doughs are forgiving and easy to shape. They won't give you big, open holes, but they produce incredibly chewy, satisfying bread. This is where most people should start.
Balanced crumb. Moderately open.
Common uses: Classic sourdough loaves, sandwich bread, country bread
This is the sweet spot for everyday baking. Most sourdough recipes you'll find online fall in this range. The dough is workable, shapes well, and produces a loaf with good oven spring and a nice mix of open and tight crumb.
Open, airy crumb. Sticky dough.
Common uses: Artisan sourdough, ciabatta-style, focaccia
High hydration is where you get those Instagram-worthy open crumb shots. But it requires more experience - the dough is sticky, harder to shape, and less forgiving. Master the basics at 70% before pushing higher.
Very open, custard-like crumb. Batter-like dough.
Common uses: Focaccia, pan loaves, ciabatta
At this level, you're working with something closer to a thick batter. Focaccia at 80-85% is a great entry point - it bakes in a pan so shaping doesn't matter, and the results are incredible.
Whole grain flours contain the bran and germ, which absorb significantly more water than white flour. A dough at 75% hydration with 100% whole wheat will feel much drier than the same hydration with bread flour. When using whole grains, you'll typically want to add 5-10% more water.
Bread flour (12-14% protein) absorbs more water than all-purpose flour (10-12% protein). If you switch flour brands or types, you may need to adjust your water. Always hold back 20-30g of water and add it gradually during mixing - you can always add more, but you can't take it out.
Mixing just flour and water and letting it rest for 30-60 minutes before adding salt and starter (the autolyse) allows the flour to fully hydrate. This makes the dough easier to handle and improves gluten development, especially at higher hydrations.
Browse our recipes - each one lists its hydration percentage so you know exactly what to expect.
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