Sourdough hydration calculator
Calculate the true hydration of your sourdough.
Your starter contains both flour and water. Enter the main dough and starter separately; the calculator combines them correctly.
Works with stiff and liquid starters too.Your dough
Enter the main dough and starter
Enter only the flour and water added directly to the main dough. Add the starter separately below.
100% means equal weights of flour and water.
True ratio
Hydration including starter
Effective hydration75%
- Total flour
- 500 g
- Total water
- 375 g
- Flour from starter
- 50 g
- Water from starter
- 50 g
- Starter as % of total flour
- 20%
Why is this different from water ÷ flour?
Starter is not separate from flour and water: it contains both. At 100% hydration, 100 g starter contributes 50 g flour and 50 g water.
Salt and other dry ingredients do not change hydration. Liquids such as milk or egg need a more detailed formula.
Want to calculate the full recipe?
Use the advanced calculator for salt, preferments, extra ingredients and a target dough weight.