Hydration puts water against flour
Dough hydration is water weight divided by flour weight, multiplied by 100. It uses flour as the denominator, not total dough weight. The calculation assumes weighed water and flour; volume cups are too variable for a formula intended to compare dough handling between batches.
Five hundred grams of flour with 350 g water
The displayed values give 350 ÷ 500 × 100 = 70% hydration. A 70% label means 70 g water for every 100 g flour. It does not mean the dough is 70% water by total weight, and it does not include the salt or yeast in the ratio.
Count water hidden in starters and soakers
A liquid starter contributes both flour and water. Ignoring its water makes the stated hydration too low; adding the water without its flour makes it too high. Record each component’s flour and water separately before calculating a final formula, particularly for sourdough or prefermented doughs.
Flour type changes the feel at one percentage
Whole-grain, rye, high-protein, and freshly milled flours absorb differently. Two doughs marked 70% can therefore feel unlike one another. Use the result as a formula description, then adjust water during mixing according to the flour, fermentation plan, and desired product.
Hydration is not a salt or yeast calculator
This page isolates the water-to-flour relationship. It cannot tell whether salt is 2%, whether yeast is appropriate for an overnight rise, or whether a dough is ready to shape. Those require additional ingredient percentages and real observation of fermentation.
When the number stops being enough
Use hydration to reproduce or compare weighed dough formulas. It is not a promise of texture, proof time, or loaf quality. Temperature, mixing, rest time, and dough development remain outside the fraction and should be documented with any successful bake.
Use the percentage to compare like formulas
A hydration figure becomes useful when flour type, whole-grain share, and mixing method accompany it. Comparing an enriched brioche with a lean country loaf by water percentage alone can hide eggs, butter, or milk that change the dough. Keep those ingredients in the formula record instead of treating one percentage as the whole recipe. The same percentage is most informative when the flour and process are held constant between bakes.
Calculate a mixed starter explicitly
Consider 400 g flour and 250 g water in a final mix plus 100 g of a 100% hydration starter. That starter contributes 50 g flour and 50 g water, giving 450 g flour and 300 g water in total. Hydration is 300 ÷ 450 × 100, or 66.7%, not 62.5% from ignoring starter water and not 75% from adding water without its flour. Writing the components first prevents a plausible but wrong label.
Reserve water with a measured plan
If a nominal 70% dough uses 500 g flour, its target water is 350 g. A baker might mix 320 g first and hold back 30 g while assessing absorption. If all 30 g is later added, the recorded hydration remains 70%; if only 20 g is added, actual water is 340 g and hydration is 68%. This turns a tactile adjustment into a reproducible formula instead of a memory of “a splash more.”
Hydration does not state dough temperature
Water temperature, room temperature, flour temperature, and mixing time affect fermentation and handling without changing the hydration fraction. A cool 70% dough and a warm 70% dough may develop on different schedules. Keep the percentage with the flour type, starter state, mix temperature, and fermentation plan. The number is a useful coordinate for a formula, not a complete description of the dough system.
Use flour weight to scale a hydration target
At 70% hydration, 750 g flour calls for 525 g water because 750 × 0.70 equals 525. That forward calculation is useful when a baker starts from a desired flour quantity, while the converter works backward from weighed flour and water. Keep the percentage as a decimal only during arithmetic; the recipe record should state both the percentage and the actual gram weights so another baker can verify the total.
Account for non-water liquids deliberately
Milk, juice, eggs, and fats contain water but are not identical to poured water in dough behaviour. This simple page accepts flour and water weights, so it does not infer their water contribution. A formula using those ingredients needs a defined convention for total hydration and a full ingredient record. Do not add their entire mass as water without stating that approximation.
Record water additions during mixing
A baker who holds back 25 g of the displayed 350 g water has actually mixed 325 g with 500 g flour, or 65% hydration, until the remainder is incorporated. Mark the held-back amount in the formula instead of continuing to call the dough 70%. This makes a later adjustment intelligible: the final percentage can be restored only after all planned water is included. The calculator reports the weights entered, not a target hidden in the bowl.