Dough hydration calculator
Calculate hydration including the flour and water held inside a levain — the step most sourdough calculators leave out.
What it answers
What is my dough’s true hydration once the levain is counted?
What it assumes
- Hydration is water as a percentage of TOTAL flour weight, including the flour inside any levain or preferment.
- A levain at h% hydration divides as flour = weight ÷ (1 + h/100), with the remainder as water.
- Every weight is in the same unit. The arithmetic is unit-agnostic; mixing grams and ounces is the user’s error.
- Only water counts as water. Milk, eggs, butter and oil are NOT counted, because their water content varies by product and guessing would produce an authoritative-looking invention.
Your formula
The answer
76% hydration
A wet dough. Expect it to stick, to need folds rather than kneading, and to reward a banneton or a tin. This is the range most open-crumb sourdough sits in.
Ignoring the levain would have given 70% — out by 6 percentage points. That gap is why two recipes claiming the same hydration can produce visibly different doughs.
The working
How this was calculated
Flour inside the levain
- Formula
F(levain) = L ÷ (1 + h ÷ 100)- With your numbers
F(levain) = 200 ÷ (1 + 100 ÷ 100)- Result
- 100 g
Water inside the levain
- Formula
W(levain) = L − F(levain)- With your numbers
W(levain) = 200 − 100- Result
- 100 g
Total flour
- Formula
F = dough flour + F(levain)- With your numbers
F = 400 + 100- Result
- 500 g
Total water
- Formula
W = dough water + W(levain)- With your numbers
W = 280 + 100- Result
- 380 g
Hydration
- Formula
H = W ÷ F × 100- With your numbers
H = 380 ÷ 500 × 100- Result
- 76%
What ignoring the levain would have told you
- Formula
H(naive) = dough water ÷ dough flour × 100- With your numbers
H(naive) = 280 ÷ 400 × 100- Result
- 70% — out by 6 points
What the symbols mean
- H — hydration, as a percentage of total flour weight
- W — total water — dough water plus the water inside the levain
- F — total flour — dough flour plus the flour inside the levain
- L — total weight of levain added
- h — the levain's own hydration, as a percentage
A worked example
Take 400 g of flour and 280 g of water in the dough, plus 200 g of levain kept at 100% hydration.
The levain divides as 200 ÷ (1 + 1) = 100 g of flour and 100 g of water. Total flour is 400 + 100 = 500 g; total water is 280 + 100 = 380 g. Hydration is 380 ÷ 500 × 100 = 76%.
The dough figures alone would have said 280 ÷ 400 × 100 = 70%. Six percentage points is the difference between a dough you can shape confidently and one that spreads.
What it cannot tell you
It does not count the water inside other ingredients. A formula rich in milk, egg or butter carries more water than this figure shows, and a professional formulation may account for that.
There is no correct hydration. A stiff bagel dough and a very wet ciabatta are both right for what they are, so the interpretation describes how a dough HANDLES rather than whether it is right.
Two doughs at identical hydration can behave completely differently, because flours absorb differently. Wholemeal and rye take up considerably more water than white at the same percentage.
It says nothing about process. The same percentages fermented warm for four hours and cold for eighteen are different breads.