LoafTime

Sourdough hydration calculator

Your dough’s real hydration — counting the water and flour inside your starter.
Flour
cups
Water
cups
Starter
cups
Your starter’s hydration
%
100% = equal weights of flour and water (the usual).
Hydration you want
%
For 75%, use 1 ½ cups + 2 tbsp (363 g) of water.
Total hydration
72.7%
Without the starter it looks like 70.0%
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How it works

Hydration is the water as a percentage of the flour. A starter is half flour and half water (at 100% hydration), so it changes the real number.
Higher hydration makes a more open, stickier dough; 65–70% is easy to handle, 75% and up takes practice.

Questions

Does the starter count toward hydration?

Yes. A 100% hydration starter is half flour, half water. 500 g flour + 350 g water alone is 70%, but with 100 g of starter the dough is really 72.7%.

What hydration should a beginner use?

Start around 65–70%: the dough is easier to shape. Go higher once shaping feels easy — the crumb gets more open.

Why does my dough feel wetter than the recipe says?

Flours drink different amounts of water: whole wheat and fresh flour take more, some all-purpose flours less. Hold back a little water and add it if the dough feels stiff.

Sources

Ingredient Weight Chart
King Arthur Baking
Checked September 30, 2026. The figures are the bakers’; the model and the words are ours. Watch the dough, not the clock.

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All sourdough tools
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