Sourdough Hydration Calculator
Most hydration calculators ignore your starter — this one doesn't. It counts the flour and water inside your starter, so you get your dough's true hydration.
Aiming for a specific hydration?
How dough hydration is calculated
Hydration is total water divided by total flour, as a percentage:
hydration = (water + starter water) ÷ (flour + starter flour) × 100
The catch is the starter. A starter at 100% hydration is half flour, half water by weight — so 100 g of it adds 50 g flour and 50 g water to your dough. Skip that step and a "75% hydration" recipe can really be several points off, which is the difference between a dough that holds its shape and one that spreads on the peel.
What hydration should sourdough be?
| 60–65% | Firm, easy-to-shape dough. Sandwich loaves, beginners' loaves, bagels at the low end. |
|---|---|
| 65–75% | The classic artisan range. Good oven spring and an open-but-manageable crumb. |
| 75–85% | High hydration. Very open crumb, thin crisp crust — but sticky dough that demands practiced handling. |
| 85%+ | Ciabatta and focaccia territory. Handled with wet hands and a scraper, not shaped tightly. |
Flour matters as much as the number: strong bread flour and whole grains absorb more water, so a 75% whole-wheat dough handles like a 70% white-flour dough. When trying a new flour, start 5 points lower than your target and work up.
Stiff starter? No problem
If you keep a stiff levain (say 50% hydration), just set the starter hydration field to match. The calculator splits it correctly — 150 g of 50% starter is 100 g flour and 50 g water.