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SourdoughRatio

Sourdough Hydration Calculator.

Enter the flour, water and starter in your dough and see its true hydration, with the flour and water inside your starter counted. Works in grams, ounces and pounds.

Added, not counting starter
g
Added, not counting starter
ml
Active starter in the dough
g
100% = equal flour and water
%

Your dough

Hydration

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Total flour
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Total water
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Without starter
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How it works

How sourdough hydration is calculated

Hydration is the amount of water divided by the weight of flour, shown as a percentage. 350 ml of water with 500 g of flour is 70%. In sourdough the starter complicates this, because it is part flour and part water. A fair hydration figure counts both.

starter flour = starter ÷ (1 + starter hydration)
starter water = starter − starter flour

total flour   = flour + starter flour
total water   = water + starter water

hydration     = total water ÷ total flour × 100
  • Starter hydration is the water in your starter divided by its flour. Fed with equal weights of each, it is 100%.
  • Without starter shows the simple figure, water ÷ flour, so you can compare with calculators that ignore the starter.

Worked example

500 g flour, 350 ml water, 100 g starter at 100% hydration, 10 g salt.

Worked example
Flour in the starter50.0 g
Water in the starter50.0 ml
Total flour550.0 g
Total water400.0 ml
Hydration72.7%

Ignoring the starter, the same dough works out to 70%.

Rules of thumb

What hydration should I aim for?

Typical ranges for sourdough bread. Flour type, kitchen temperature and technique all move these, so treat them as starting points.

HydrationDough feelCommon uses
Under 60%StiffBagels, some enriched breads
60 – 68%Firm, easy to shapeBaguettes, beginner loaves
68 – 75%Soft, standardEveryday country loaf
75 – 82%Wet and stickyOpen-crumb loaves, ciabatta-style breads
Over 82%Very wetExperienced bakers, strong flour

Technique

Hydration and stretch and folds

There is no formula that turns hydration into a stretch-and-fold schedule, so this page does not pretend to give one. What hydration does change is how slack the dough is, and that changes how many folds it benefits from. These are common starting points, to be adjusted to how your dough feels and how warm your kitchen is.

HydrationTypical approach
Under 68%Two or three sets of stretch and folds, about 30 minutes apart, early in bulk fermentation.
68 – 75%Three or four sets about 30 minutes apart during the first couple of hours.
75 – 82%Four sets, with wet hands and a gentle touch. Some bakers use coil folds for slack dough.
Over 82%Several gentle sets, spaced to match how quickly the dough tightens up.

FAQ

Hydration questions

How do I calculate sourdough hydration?
Divide the weight of water by the weight of flour and multiply by 100. If a dough has 1,000 g of flour and 750 ml of water, the hydration is 75%. With sourdough, the starter holds flour and water too, so add the starter’s share of each to the totals first. This calculator does that for you.
Should the starter count toward hydration?
Yes, in most baker’s formulas it does. A starter fed equal weights of flour and water is half flour and half water by weight, so 100 g of starter adds 50 g of flour and 50 ml of water. With 500 g of flour, 350 ml of water and 100 g of 100% starter, the overall hydration is 72.7%. Ignoring the starter would give 70%. The calculator shows both numbers so you can see the difference.
What is a good hydration for sourdough bread?
Around 65–70% is firm and forgiving, which suits beginners. 70–75% is a standard country loaf with a fairly open crumb. 75–82% is wet and sticky, and works best with strong bread flour and some practice. Above that the dough is very hard to shape. These are guides, not rules, because flour and kitchen conditions vary.
What does 75% hydration mean?
It means there are 75 ml of water for every 100 g of flour. For 500 g of flour that is 375 ml of water. 75% is a popular choice for sourdough because it gives a soft dough and an open crumb without being too difficult to handle.
How do I raise or lower hydration?
Change the water by a percentage of the flour. To go from 70% to 75% with 500 g of total flour, add 25 ml of water (5% of 500 g). To go from 75% to 70%, remove 25 g. Raise it a few points at a time so you can see how the dough changes.
Does whole wheat flour need more water?
Usually yes. Whole grain flours absorb more water than white flour, so the same hydration feels stiffer. Many bakers add a few extra percentage points when they add whole wheat or rye, then adjust to how the dough feels.
How does hydration affect stretch and folds?
A wetter dough is slacker, so it usually benefits from more sets of stretch and folds, done gently with wet hands. A stiffer dough builds strength faster and often needs fewer. The table on this page gives common starting points. This calculator does not set a folding timer, and your own dough and room temperature matter more than any chart.
Why does another sourdough hydration calculator give a different number?
The usual reason is the starter. Some tools divide only the added water by the added flour and ignore the flour and water inside the starter. Others count them. Neither is a mistake, but the numbers will not match. This calculator shows the overall hydration with the starter counted and the figure without it.