Bread Hydration Calculator

How to use the Bread Hydration Calculator

1. Enter the flour and pick its unit.
2. Enter the water and pick its unit.
3. Enter the sourdough starter / levain and pick its unit – Enter 0 for yeasted dough.
4. Enter the starter hydration.
5. Enter the salt and pick its unit.
6. Enter the target hydration.
7. Press Calculate. The result updates automatically as you type, and you can switch the result unit at any time.

About the Bread Hydration Calculator

Hydration is the weight of water divided by the weight of flour, and it is the single number that best describes how a dough will feel and bake. Bakers often forget that a sourdough starter is itself flour and water; a 100% hydration starter is half of each, so ignoring it can make a recipe seem drier than it really is.

Whole-grain flours absorb more water, so a 75% whole wheat dough can feel like a 70% white dough. Milk is about 87% water and eggs about 75%, so count them proportionally if you use them. Salt is usually 1.8–2.2% of the total flour.

Formula

starter flour = starter ÷ (1 + starter hydration)
starter water = starter − starter flour
hydration = (water + starter water) ÷ (flour + starter flour) × 100%

With 500 g flour, 350 g water and 100 g of 100% starter: total flour 550 g, total water 400 g, hydration 72.7%.

Example calculation

Using the default values:

• Flour = 500 g
• Water = 350 g
• Sourdough starter / levain = 100 g
• Starter hydration = 100%
• Salt = 11 g

the calculator returns:

• Total hydration: 72.7%
• Dough type: High hydration (rustic sourdough, country loaves)
• Total flour: 550 g
• Total water: 400 g
• Salt (% of flour): 2%
• Total dough weight: 961 g

Frequently asked questions

Last updated: 2026-10-12 · Category: Cooking calculators