Sourdough Hydration Calculator
Find the true hydration of a dough you already mix, or build a new dough to an exact target hydration. Either way, your starter is split into flour and water and counted in, so the number is the real one.
Balanced
Total flour 550 g (incl. 50 g from starter) · total water 375 g (incl. 50 g from starter)
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How to use the sourdough hydration calculator
- Measure my hydration: enter your flour, water, and starter weights. The tool returns the true total hydration with the starter folded in.
- Build to a target: enter your flour, a target hydration, your starter percentage, and salt. The tool returns the water to add, starter, and salt.
- If your starter is not 100 percent hydration, set the starter hydration field and the math adjusts.
Why the starter has to be counted in
Hydration is total water divided by total flour, written as a percentage. The catch with sourdough is that the starter is itself flour and water. A 100 gram starter at 100 percent hydration is 50 grams of flour and 50 grams of water. If you ignore it, your hydration figure is wrong, often by several points. This calculator always splits the starter and adds both halves to the totals, so two bakers using the same recipe land on the same number.
Choosing a hydration level
Lower hydration doughs (about 65 percent) are firmer, easier to shape, and forgiving for beginners; they bake into a tighter, sandwich-friendly crumb. Mid hydration (70 to 75 percent) is the sweet spot for an open, airy crumb that still handles well. High hydration (80 percent and up) can produce a dramatic, holey crumb but is sticky and demands good technique and strong flour. If you are new, start near 70 percent and raise it as your shaping improves.
Inoculation and timing
Inoculation is the amount of starter relative to the flour. A higher percentage means more active yeast and a faster rise; a lower percentage means a slower, more flavorful fermentation. Around 20 percent is a dependable default at room temperature. In a warm kitchen, drop the inoculation or shorten the bulk ferment; in a cold kitchen, raise it or extend the time. The ingredient weights stay the same; only the schedule changes.
Salt
Salt is typically 2 percent of the total flour. It seasons the loaf and strengthens the gluten, which improves structure and slightly slows fermentation. The build mode adds it for you based on the total flour, including the flour from your starter.
Gear for better sourdough
Affiliate links · we may earn a commission- Kitchen scale (0.1 g) →Hydration math only works if you weigh. A precise scale is the first tool to buy.
- Banneton proofing basket →Supports the dough during its final rise and leaves the classic spiral.
- Dutch oven →Traps steam for a tall rise and crackly crust in a home oven.
- Bread lame →Scores the loaf so it opens cleanly where you want it to.
Frequently asked questions
Does the starter count toward hydration?
Yes. A starter is part flour and part water, so it must be included. This calculator splits your starter into its flour and water and folds both into the total, which is why its hydration figure is the true one.
What hydration should sourdough be?
A beginner-friendly sourdough is around 65 to 70 percent. 70 to 75 percent gives a more open crumb but a stickier dough; above 80 percent is high-hydration territory that needs careful handling. The default target here is 75 percent.
What is inoculation or starter percentage?
Inoculation is how much starter you use, expressed as a percent of the flour. Around 20 percent is common. More starter ferments faster; less starter ferments slower and develops more flavor over a longer rise.
My starter is not 100 percent hydration, does that matter?
Yes, and you can set it. A stiff starter (for example 50 percent) carries less water, so the math changes. Enter your starter hydration and the calculator adjusts the flour and water split automatically.
How do I raise or lower hydration?
Use the build mode, set your flour and target hydration, and the calculator tells you exactly how much water to add after accounting for the water already in your starter.
Also try the pizza dough calculator for yeasted pizza in any style.