You're scaling a sourdough loaf recipe for a cafe batch. The head baker has given you a formula in baker's percentages, but the flour weight changes every morning. Before mixing, you need to calculate today's exact water, salt and yeast weights from the flour on the scale.
Ingredient % = (Ingredient weight ÷ Flour weight) × 100
Flour is always 100%. All other ingredients are expressed as a percentage of the flour weight. This makes it easy to scale recipes and compare formulas regardless of batch size.
1 What this calculator does
Calculates baker's percentages for each ingredient relative to the flour weight (which is always 100%). Enter the flour, water, salt, yeast and any other ingredient weight to see each as a baker's percentage and classify the hydration type. Shows total dough weight.
2 Formula & professional reasoning
Baker's percentage = (Ingredient weight / Flour weight) x 100
Flour is always 100% -- all other ingredients are expressed relative to flour weight
Hydration = Water weight / Flour weight x 100
Hydration types: <60% Very stiff (bagels) | 60-70% Medium (sandwich bread) | 70-80% High (ciabatta) | 80%+ Very high (sourdough, baguettes)
Baker's percentages allow a recipe to be scaled to any batch size while keeping ingredient ratios constant. Because flour is the base (100%), all percentages remain unchanged whether you bake 1 loaf or 100 loaves -- you simply multiply each percentage by the new flour weight. This makes baker's percentages the universal language of professional baking. Hydration percentage directly controls dough workability and final crumb structure -- higher hydration produces more open, irregular crumb.
3 Worked examples
⚠️ Illustrative example only — not clinical or professional instruction.
Water%: 325/500 x 100 = 65.0% | Salt%: 9/500 x 100 = 1.8% | Yeast%: 4/500 x 100 = 0.80% | Total dough: 500+325+9+4 = 838gWater%: 780/1000 x 100 = 78.0% | Salt%: 20/1000 x 100 = 2.0% | Yeast%: 3/1000 x 100 = 0.30% | Other (oil)%: 30/1000 x 100 = 3.0% | Total: 1,833gScale factor: 2,200/500 = 4.4x | New water: 500 x 0.70 x 4.4 = 1,540g | Original salt 1.8%: 2,200 x 0.018 = 39.6g | Original yeast 0.80%: 2,200 x 0.008 = 17.6g4 Sanity check
5 Common errors
| Error | Cause | Consequence | Fix |
|---|---|---|---|
| Using total recipe weight instead of flour weight as the base | Treating baker's % like standard cooking percentage | All percentages wrong -- cannot compare to or scale from professional recipes | Flour is always the denominator. Baker's percentage = (ingredient / flour) x 100. Not (ingredient / total dough) x 100. |
| Forgetting to adjust leavening agents when scaling large batches | Scaling yeast proportionally for very large batches | Over-leavened bread with off flavour at very large scales -- yeast becomes less efficient at very high quantities | For batches over 10kg flour, reduce yeast percentage slightly (use 0.6-0.7% instead of 0.8-1.0%). Enzyme activity and dough temperature management become more critical at large scale. |
| Calculating hydration without including all liquid ingredients | Counting water but forgetting milk, eggs or oil | Actual dough much softer than the calculated hydration suggests | All liquids contribute to effective hydration. Milk, buttermilk and eggs are approximately 90% water by weight. Add them to the water weight before calculating hydration. |
| Applying baker's percentage to non-flour bases | Using the formula for recipes based on sugar, chocolate or other bases | Wrong percentages -- unworkable formula | Baker's percentage applies to bread and pastry recipes where flour is the structural base. For confectionery recipes based on chocolate, sugar or cream, standard weight-for-weight percentages apply. |
6 Reference & regulatory links
7 Professional workflow
Common tools used alongside this one: