Baker's Percentage Calculator
Flour is always 100%. Every other ingredient's weight is shown as a percentage of the flour weight — the standard way bakeries write and scale formulas. Enter weights below, or edit the flour weight to scale the whole formula.
| Ingredient | Weight (g) | % of flour | |
|---|---|---|---|
| Flour | 1000 | 100% | |
| 65.0% | |||
| 2.0% | |||
| 0.7% |
If one of your ingredients is named "water" (any case), its percentage of flour is also shown here as hydration — the single most-referenced ratio in bread baking.
Scale this formula
Change the flour weight above (or enter a target total dough weight below) and every ingredient weight recalculates automatically, holding percentages constant.
How it works
Every ingredient is divided by the total flour weight and multiplied by 100. Flour is therefore always 100%, and the other percentages add up to more than 100%. The sum of all the percentages is the formula's total percentage: for 100% flour, 70% water, 2% salt and 1% yeast it is 173%.
Going the other way, a target dough weight divided by the total percentage (as a decimal) gives the flour weight: 2,595 g ÷ 1.73 = 1,500 g of flour. Each ingredient is then flour × its percentage. King Arthur Baking calls the same number the formula conversion factor and rounds it up slightly, because a little extra dough is better than a short batch.
The "true" percentage of an ingredient, its share of the whole dough, is its baker's percentage divided by the total percentage. Water at 70% of the flour is 70 ÷ 173 = 40.5% of the dough. Use true percentages only when you need a share of the dough, for example to check nutrition labels; bakers write and scale formulas in baker's percentages.
Worked example
A basic lean dough: 1,000 g flour, 700 g water, 20 g salt and 10 g instant yeast.
Water = 700 ÷ 1,000 = 70% (that is also the hydration), salt = 2%, yeast = 1%. Total dough weight is 1,730 g, or 173% of the flour.
To make 2,595 g of dough instead, divide by 1.73 to get 1,500 g flour — then water 1,050 g, salt 30 g and yeast 15 g. The percentages never change.
Common mistakes
- Using total dough weight as the 100%. The base is always the flour, never the dough.
- Forgetting the flour and water inside a starter or poolish. In an overall formula they count toward the flour and the water; leaving them out makes a 70% dough look like 60%.
- Leaving out a second flour. Whole wheat, rye or semolina are part of the 100% too.
- Mixing units. Weigh everything in the same unit (all grams or all ounces); the percentages only work by weight, not by cups or spoons.
- Rounding small ingredients too hard. On a 500 g batch, 1.2% yeast is 6 g; rounding it to 10 g is a two-thirds increase.
When not to rely on it
Baker's percentages describe proportions, not technique. Two doughs with identical percentages can behave very differently if the flours absorb water differently, which is why a formula from another country or miller may need its water adjusted.
For recipes with almost no flour (meringues, custards, some gluten-free cakes) the flour base becomes tiny and the percentages stop being useful. Write those by weight instead.
Frequently asked questions
What is baker's percentage?
A way of writing a formula where flour is always 100% and every other ingredient is a percentage of the flour weight. Because of that, the percentages add up to more than 100%.
How do I calculate hydration?
Divide the water weight by the flour weight and multiply by 100. 700 g water to 1,000 g flour is 70% hydration. Include other liquids such as milk only if you want the effective hydration.
What if the recipe uses two kinds of flour?
Add all the flours together — that total is the 100%. Each flour can then be shown as its share, for example 80% bread flour and 20% whole wheat.
Why do bakers use percentages instead of cups?
Percentages scale cleanly to any batch size and make formulas easy to compare. Volume measures like cups vary too much for flour to be reliable.
How do I convert a recipe in cups to baker's percentages?
Weigh each ingredient first, or use the weights the recipe author gives. Cup weights for flour vary with how the cup is filled, so a percentage built from a guessed cup weight is only as good as the guess.
What is the difference between baker's percentage and true percentage?
Baker's percentage divides by the flour weight; true percentage divides by the total dough weight. 70% water in baker's terms is 40.5% of a dough whose percentages total 173%.
Read the guide
Sources
- King Arthur Baking — Baker's percentage (pro reference) — definition, formula conversion factor, white bread and poolish examples
- Wikipedia — Baker percentage — true percentage and formula percentage, hydration ranges by dough type
Last reviewed: 2026-10-25. Found an error? Email contact@bakerymath.com.
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