The baker's percentage calculator turns hydration, starter and salt percentages into grams or ounces, shows the true hydration of a recipe you already use, and scales it to any number of loaves.
Open the baker's percentage calculatorWhat baker's percentage means
Bakers write recipes with the flour as 100% and every other ingredient as a percentage of the flour's weight. Not of the whole dough: of the flour. So the percentages add up to more than 100, and that is expected.
Ingredient % = ingredient weight ÷ total flour weight × 100
A simple loaf with 1,000 g of flour:
| Ingredient | Weight | Baker's % |
|---|---|---|
| Flour | 1,000 g | 100% |
| Water | 700 g | 70% |
| Salt | 20 g | 2% |
| Instant yeast | 7 g | 0.7% |
| Total | 1,727 g | 172.7% |
The point is that the recipe no longer depends on batch size. 70% water means 70 g per 100 g of flour, whether you bake one loaf at home or forty in a bakery, and two recipes can be compared at a glance.
When a recipe uses several flours, all of them together are the 100%. A loaf with 800 g of white flour and 200 g of wholemeal is 80% white and 20% wholemeal, and the water is measured against the full 1,000 g.
Hydration
Hydration is simply the water's baker's percentage: water ÷ flour × 100. The loaf above is a 70% hydration dough. Hydration is the number that tells you most about how a dough will behave: higher hydration means a softer, stickier dough, usually a more open crumb, and a dough that needs more strength from folding to hold its shape.
Milk, eggs and other liquids also bring water. Whole milk is about 88% water and a whole egg about 76%, so a baker working out the real hydration of an enriched dough counts that water too. For lean sourdough, the only extra water usually comes from the starter.
Counting the starter: the part most recipes skip
A sourdough starter is flour and water. At 100% hydration it is equal weights of each; a stiff starter at 50% is two parts flour to one part water. When you add starter to a dough, you add its flour and water too, and the true hydration has to include them.
Starter flour = starter weight ÷ (1 + starter hydration ÷ 100). Starter water = the rest.
Take a common recipe: 450 g flour, 300 g water, 100 g starter at 100%, 9 g salt.
| Without the starter | With the starter counted | |
|---|---|---|
| Flour | 450 g | 450 + 50 = 500 g |
| Water | 300 g | 300 + 50 = 350 g |
| Hydration | 66.7% | 70% |
| Salt | 2% | 1.8% |
The difference is 3.3 points, enough to feel in the dough. With a stiff starter it goes the other way: 500 g flour, 330 g water and 150 g of 50% starter is 100 g more flour and only 50 g more water, so 66% becomes 380 ÷ 600 = 63.3%.
Recipes also disagree on what the starter percentage is measured against. “20% levain” can mean 20% of the flour you add (100 g of starter for 500 g of flour) or 20% of all the flour including the starter's. The weights come out a few grams apart. If a recipe gives grams, trust the grams; the calculator has a switch for either reading.
Building a recipe from percentages
Say you want three 750 g loaves at 78% hydration, with 15% starter (100% hydration, of total flour) and 2.2% salt.
- Add up the percentages. Flour 100 + water 78 + salt 2.2 = 180.2%. The starter isn't added, because its flour and water are already inside the 100 and the 78.
- Find the total flour. Dough 2,250 g ÷ 1.802 = 1,249 g of flour in total.
- Work out the starter. 15% of 1,249 g = 187 g, of which 94 g is flour and 94 g water.
- Take the starter out of the flour and water. Flour to add: 1,249 − 94 = 1,155 g. Water: 78% of 1,249 = 974 g in total, so 974 − 94 = 880 g to add.
- Salt. 2.2% of 1,249 g = 27.5 g.
| Weigh out | Grams | Ounces |
|---|---|---|
| Flour | 1,155 g | 40.74 oz |
| Water | 880 g | 31.05 oz |
| Starter | 187 g | 6.61 oz |
| Salt | 27.5 g | 0.97 oz |
| Dough | 2,250 g | 79.37 oz |
Scaling an existing recipe is easier still: divide the new dough weight by the old one and multiply every ingredient by that factor. All the percentages stay the same. Some dough always sticks to the bowl, so add 1% to 2% if each loaf must hit its weight.
Typical hydration by kind of bread
These are common starting points with mostly white bread flour, not rules:
| Bread | Hydration | What it's like |
|---|---|---|
| Bagels, pretzels | 55–60% | Stiff, smooth, easy to shape tightly |
| Sandwich loaf | 60–65% | Soft, even crumb that slices well |
| Baguette | 65–75% | Thin crust, irregular holes |
| Country sourdough | 70–80% | Open crumb, needs folds for strength |
| Ciabatta, focaccia | 75–85% or more | Very soft, shaped gently or baked in a tin |
If you are new to sourdough, start near 68–70%. A slightly stiffer dough is much easier to shape, and you can raise the water 2% at a time once handling it feels easy.
Why the same percentage feels different
- Wholemeal and rye drink more water. Bran and rye's gums absorb water, so a 75% wholemeal dough feels stiffer than a 75% white one. Many bakers add 5–10 points for a mostly wholemeal loaf.
- Flour varies by brand and country. Stronger, higher-protein bread flour holds more water than plain or all-purpose flour, so a recipe written for one may feel wet with another.
- Inclusions change the feel. Seeds soaked in water bring that water with them; dried fruit takes some away. Bakers often treat a soaker's water separately from the dough's.
- Hold some water back. With an unfamiliar flour, keep 5% of the water aside and add it during mixing if the dough needs it.
Need a plain percentage for something else, such as the salt in a brine? The percentage calculator does any percent of a number.
Sources
- Wikipedia: Baker percentage. Flour as 100%, hydration, and percentages of multiple flours
- King Arthur Baking: Professional formulas. Bakery formulas written in baker's percentages
- USDA FoodData Central. Water content of whole milk (about 88%) and raw whole egg (about 76%)