Hydration Calculator
This calculator finds a dough's hydration percentage from flour and water weight, or calculates the water needed for a target hydration.
It works for any yeasted or sourdough recipe, not just sourdough specifically.
Because hydration is calculated by weight rather than volume, the calculator is most accurate when starting from gram measurements rather than a cup-based recipe that hasn't been converted first.
How to Use the Hydration Calculator
Reference Values
The Science Behind It
Hydration percentage is water weight divided by flour weight, times 100. It's the single biggest factor in dough texture — higher hydration means more steam during baking, which creates larger, irregular air pockets. Source: King Arthur Baking.
King Arthur Baking's hydration guidance notes that flour protein content affects how much water a dough can absorb before becoming too slack to shape, meaning the same hydration percentage can feel different across flour types.
Professional bread formulas often express hydration to a precise decimal point (like 72.5%) since even small changes measurably affect crumb structure at a commercial baking scale.
Where This Shows Up
Home bakers troubleshooting a dough that's too sticky or too dry frequently use this calculator to check whether their measured hydration matches what the recipe intended.
Bakers experimenting with a new bread style, like moving from a lean baguette to a wetter ciabatta, use hydration percentage as the primary variable to research and adjust.
Bread recipe archives and community cookbooks increasingly list hydration percentage alongside traditional cup measurements, letting more experienced bakers quickly gauge a recipe's expected texture before making it.
A Worked Example
Say you're converting an old family recipe that lists '4 cups flour, 1½ cups water' into a percentage. Using flour's density (125g/cup), 4 cups is 500g; 1½ cups of water is about 355g. Divide 355 by 500 and multiply by 100 to get roughly 71% hydration — a fairly standard sandwich-bread level, useful context even though the original recipe never stated it directly.
Low vs High Hydration Dough
| Low Hydration (50-65%) | High Hydration (75%+) | |
|---|---|---|
| Handling | Easier to shape | Sticky, needs technique |
| Crumb | Tighter, denser | Open, irregular |
| Examples | Bagels, sandwich bread | Ciabatta, focaccia |
Common Mistakes
- Calculating hydration from volume-based cup measurements instead of weight, which introduces significant inaccuracy compared to a gram-based calculation.
- Forgetting to include liquid contributions from eggs, milk, or a sourdough starter when calculating total dough hydration.
- Assuming a stated hydration percentage from one flour type will behave identically with a different flour, without adjusting for absorption differences.
- Calculating hydration only from the main flour and water in a recipe while ignoring smaller liquid contributions like milk or egg.
- Not accounting for flour that's been stored in a humid environment, which can already carry extra moisture before water is even added.
Related Calculators
Sourdough Calculator
This calculator works out your dough's hydration percentage from flour and water weight, or the reve
Pizza Dough Calculator
This calculator scales flour, water, salt, and yeast to match how many pizzas you want to make and t
Focaccia Calculator
This calculator scales focaccia dough — flour, water, oil, and salt — to fit your specific pan size.
Bagel Calculator
This calculator scales bagel dough ingredients — flour, water, malt, and yeast — for any number of b
Frequently Asked Questions
How is hydration percentage calculated?+
Divide total water weight by total flour weight, then multiply by 100.
Does hydration include eggs or milk?+
Yes, any liquid in the dough should count toward total hydration, adjusted for the liquid's water content.
Does hydration percentage need to be exact?+
For home baking, being within a few percentage points is usually fine. Precision matters more for professional or highly reproducible recipes.
Can hydration be too high for a home oven?+
Very high hydration doughs (above 90%) can be difficult to shape and bake evenly without professional steam-injection ovens, though they're still achievable at home with practice.
Can hydration percentage exceed 125%?+
It's uncommon but possible for very wet specialty doughs, though handling becomes extremely difficult above that range without advanced technique.