Levain Build Calculator
A levain is a preferment — built from a small portion of ripe starter and allowed to reach peak activity before mixing into the final dough. Use the main calculator below to set levain percentage and hydration; the recipe output shows the levain weight you need to build.
- Flour to add
- 450 g
- Water to add
- 325 g
- Salt
- 10 g
- Levain @ 100%
- 100 g
- Total dough
- 885 g
- Effective hydration
- 75%
How the math works
Total water = flour × hydration %. Your levain contributes 50 g flour + 50 g water — both count toward the totals. You add only the remainder as fresh flour and water.
Salt % is computed on total flour weight, not final-dough flour.
Levain size vs fermentation speed
- 10-15% levain: slower fermentation (5-6h bulk at 76°F), milder flavor.
- 15-20% levain: typical artisan target (4-5h bulk at 76°F), balanced flavor.
- 20-25% levain: faster fermentation (3-4h bulk at 76°F), more pronounced sour.
- 25-35% levain: enriched doughs (panettone, brioche) where fat slows yeast.