Bread Dough Hydration, One Division Deep
500 grams of flour, 325 grams of water. Put both into the Dough Hydration Calculator and it returns 65.0%, labels it Medium Hydration, and calls the dough soft and slightly sticky. The example line under the formula is the same one, so the tool and its own documentation agree on the number.
That answer is correct. It is also the last clean number in the process, because a real bread bowl holds flour and water that are not labeled as flour and water: the starter, the milk, the egg.
The formula itself is short. Hydration % = (water weight ÷ flour weight) × 100. Nothing else goes in. Salt, yeast, sugar, and fat are measured as a percentage of flour too, but they do not move the hydration figure at all. That is why a dough can read 65% and still feel like a different dough when one recipe carries 12% butter and the other carries none.
Going the other way is the same multiplication reversed: water = flour × target ÷ 100. 500 g of flour at 72% wants 360 g of water. At 78%, 390 g.
What Each Percentage Feels Like Under Your Hand
The calculator sorts every result into a band and names a bread for it. The band matters more than the exact decimal, because your flour has an opinion the calculator cannot hear.
| Hydration | Label the calculator returns | Named for | In the bowl |
|---|---|---|---|
| under 50% | Very Low | pasta, hard pretzels | barely holds together, cracks when folded |
| 50–58% | Low | bagels, dense sandwich bread | firm, dry to the touch, springs back fast |
| 58–65% | Medium-Low | sandwich bread, dinner rolls | smooth and manageable, clears the bowl |
| 65–72% | Medium | white bread, pizza dough | soft, tacky, holds a shape but slumps slowly |
| 72–80% | High | artisan bread, ciabatta | wet, sticks to both hands, needs folds |
| 80–90% | Very High | no-knead bread, focaccia | pours more than it shapes |
| over 90% | Extremely High | some artisanal loaves | batter with structure |
Two doughs at 65% are not identical. Bread flour at 12.7% protein drinks more water than all-purpose at 11.7%, and whole wheat absorbs enough extra that bakers usually add 5 to 10 points of hydration just to match the feel of a white loaf. Target the percentage, then adjust by what the dough does in the first ten minutes.
Water for Any Batch Size
Straight from the formula, before anything else joins the bowl.
| Target | 500 g flour | 1000 g flour | 1500 g flour |
|---|---|---|---|
| 60% | 300 g | 600 g | 900 g |
| 65% | 325 g | 650 g | 975 g |
| 70% | 350 g | 700 g | 1050 g |
| 72% | 360 g | 720 g | 1080 g |
| 75% | 375 g | 750 g | 1125 g |
| 78% | 390 g | 780 g | 1170 g |
| 80% | 400 g | 800 g | 1200 g |
Water is 1 g per milliliter, so the gram figure doubles as the volume figure for tap water. That is the one liquid where the calculator’s mL field needs no thought.
The Starter Is Flour and Water the Calculator Cannot See
A 100% hydration starter is half flour and half water by weight. Fold it into a dough and you have added both, in equal measure, without writing either on the recipe card.
Work the 500 g example with 20% starter. That is 100 g of starter, so 50 g of flour and 50 g of water arrive with it. The flour you scoop is 450 g. The water you pour is 325 g. Feed only those two numbers to the calculator and it shows 72.2% for a dough that is genuinely 75%.
| Starter (100% hydration) | Starter weight | Flour inside | Water inside | Flour to scoop | Water to pour at 75% | What the calculator shows if you ignore the starter |
|---|---|---|---|---|---|---|
| 10% | 50 g | 25 g | 25 g | 475 g | 350 g | 73.7% |
| 20% | 100 g | 50 g | 50 g | 450 g | 325 g | 72.2% |
| 25% | 125 g | 62.5 g | 62.5 g | 437.5 g | 312.5 g | 71.4% |
| 30% | 150 g | 75 g | 75 g | 425 g | 300 g | 70.6% |
The 2.8-point gap between 75% and 72.2% is not cosmetic. It crosses the boundary at 72, which means a dough you built as Medium reports as High, and the shape you attempt next was chosen for a wetter dough than the one in front of you.
Two ways out. Enter the total flour and total water, starter included, which keeps the percentage honest. Or use the Sourdough Calculator, whose bread formula already subtracts the starter’s flour and water from the totals and prints “additional flour needed” and “additional water needed” as separate lines.
Milk, Egg, and Butter Carry Water Too
Enriched doughs hide water in ingredients nobody thinks of as liquid.
| Ingredient | Amount | Water it contributes |
|---|---|---|
| Whole milk | 1 cup (244 g) | 212 g |
| Large egg, out of shell | 1 (50 g) | 37 g |
| Unsalted butter | 1 tbsp (14 g) | 2.2 g |
| Honey | ¼ cup (85 g) | 15 g |
| Olive oil or melted butter | 1 tbsp (14 g) | 0 g |
A soft brioche built on 500 g of flour: 4 eggs, ½ cup milk, 8 tbsp butter. That is 148 g of water from eggs, 106 g from milk, 18 g from butter, so 272 g total, which reads 54% on the calculator.
The dough does not behave like a 54% dough. It behaves like something near 70%, slapping the bowl and refusing to firm up, because fat coats the gluten and blocks the water from hydrating it. Low hydration plus high fat is not a contradiction. It is the reason enriched doughs get judged by windowpane and feel, not by the number alone.
If you are weighing the milk anyway, remember the mL field assumes water. A cup of milk is 244 mL of volume but 251 g on the scale at 1.03 g per mL. At one cup the gap is negligible. At a quart of milk for a big batch, it is 30 g.
From Percentage to a Loaf That Fits the Pan
500 g flour, 325 g water, 2% salt at 10 g. Total dough: 835 g. A standard 9x5 inch loaf pan holds 800 to 900 g comfortably, so one batch fills one pan with a little room for oven spring.
Two pans is 1000 g flour, 650 g water, 20 g salt, and 1670 g of dough. Scale salt and instant yeast by weight, never by the spoon: instant yeast runs about 3.0 g per teaspoon, and a scooped teaspoon swings between 2.6 and 3.4 g depending on the brand and how deep you dip. For the exact yeast figure at your dough weight, the Yeast Calculator takes the dough type and rise speed and returns grams plus the active dry equivalent at 0.75 of the instant weight.
Bake a 65% pan loaf at 350°F for 35 to 40 minutes and pull it at 200 to 205°F internal. A 78% free-form loaf is a different bake: 450°F for 20 minutes, then 425°F for another 20 to 25, because the extra water has to leave the crumb or the center stays gummy.
Where the Percentage Goes Wrong Before the Oven
Flour measured in cups. One cup of all-purpose weighs 120 g at the density our charts use. Four cups is 480 g, not 500. Add the 325 g of water for a 65% dough and the real figure is 67.7%, which is the difference between a dough that clears the bowl and one that needs an extra dusting at shaping.
A wet dough mixed cool. A 65% dough mixed to 76°F finishes bulk ferment in about 2 hours at 75°F room temperature. The same dough at 68°F takes closer to 4. Hydration tells you how the dough handles. Temperature tells you when it is ready, and the two are measured separately.
Doubling a batch but not the salt. Salt at 2% of flour is 10 g on 500 g. On 1000 g it is 20 g, which is roughly 3½ teaspoons, not 3. Two percent of a doubled number is double, and eyeballing the second half is how a two-loaf bake comes out bland in one pan and correct in the other.
Try Our Free Tools
The Dough Hydration Calculator works in both directions, from flour and water to a percentage, or from flour and a target to the water you need, in grams, ounces, pounds, or milliliters. The Sourdough Calculator builds a full formula that counts starter flour and water in the totals, and the Recipe Servings Calculator rescales a dough batch when you want three loaves instead of two. Free, instant, no signup.
65% is the right answer for a pan loaf built on 500 g of flour and 325 g of water. The exception is any dough with a starter, an egg, or a cup of milk in it, where the water arriving inside those ingredients has to be counted before the percentage describes the dough you are actually holding.