Baker's-percentage instrument

The dough math, solved both ways.

Lock what you know — flour, water, starter, hydration or dough weight — and DoughMath solves the rest, counting the flour and water hidden inside your starter.

Hydration solver
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%
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True hydration75%
Total dough1018g
Flour500g
Water356g
Starter150g
Salt12g

Show the math
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  • Bi-directional — lock any three values, solve the other two.
  • True hydration — the starter’s flour + water are always counted.
  • Shows the math — no black box; copy, print or save your recipe.
  • No sign-up, works offline, your numbers never leave your browser.
The toolkit

Seven calculators, one honest method

The method

Why your starter changes the number

Baker’s percentage is the language every bread recipe is written in. It expresses each ingredient as a percentage of the total flour weight, and flour is always 100%. Water at 75% means 75 g of water for every 100 g of flour; salt at 2% means 2 g per 100 g of flour. Because everything is relative to flour, you can scale a formula to one loaf or ten and the dough behaves exactly the same.

Hydration is simply total water ÷ total flour × 100. The mistake almost every basic calculator makes is treating your sourdough starter as a single mystery ingredient. It isn’t — a starter is flour and water that have already been mixed. At 100% hydration it’s half of each, so a 150 g starter is quietly adding 75 g of flour and 75 g of water to your dough. Ignore that and the hydration on your screen won’t match the dough in your hands.

The worked example DoughMath starts you with

Take 500 g of added flour, a 150 g starter at 100% hydration, a 75% target and 2% salt. The starter splits into 75 g flour + 75 g water. So your totals are 575 g flour and a 431 g water target — but 75 g of that water is already in the starter, so you only add 356 g of water and11.5 g of salt. Total dough ≈ 1,018 g — two respectable loaves. That’s the recipe pre-loaded above; change any locked value and watch the rest re-solve.

How we calculate this. The formulas follow the standard baker’s-percentage method taught by King Arthur Baking and the Bread Bakers Guild of America: starter flour = S ÷ (1 + h), starter water = S × h ÷ (1 + h), hydration = total water ÷ total flour. The solver is unit-tested against these identities. Numbers are guidance — flour, humidity and your hands all matter, so trust your dough.
Questions bakers ask

Sourdough hydration FAQ

How do I calculate my sourdough hydration?

Hydration is total water ÷ total flour × 100. The catch: your starter is itself flour and water, so it adds to both totals. A 100% starter is half flour, half water — a 150 g starter contributes 75 g flour and 75 g water. DoughMath adds those in automatically, so the hydration you see is the true hydration of the dough, not just the water you poured in.

Is 70% hydration high for sourdough?

70% is a comfortable middle for a home baker — wet enough for an open-ish crumb, dry enough to shape without a fight. Below ~68% is easier to handle and gives a tighter crumb; 75–80%+ gives a more open crumb but demands better technique and stronger flour. Beginners usually do best starting around 68–72%.

What is a good hydration ratio for sourdough bread?

For a classic hearth loaf, 72–78% is the sweet spot with bread or high-protein flour. Enriched or sandwich loaves sit lower (60–68%); ciabatta and focaccia go higher (80%+). Whole-grain flours drink more water, so add 3–5% for every big jump in whole-grain content.

Is 60% hydration too low for sourdough?

Not at all — it just makes a firmer dough with a tighter, more uniform crumb. Bagels, pretzels and some sandwich loaves live around 55–65%. It’s a great hydration to learn shaping on because the dough holds its shape. You won’t get big open holes, and that’s by design.

How do you calculate baker’s percentage?

Every ingredient is expressed as a percentage of the total flour weight, and flour is always 100%. So water ÷ flour × 100 is your hydration %, salt ÷ flour × 100 is your salt %, and so on. Because everything is relative to flour, you can scale a recipe up or down and the ratios — and the result — stay identical.