Sourdough Calculator
Find the water, starter, salt, and total dough weights for a sourdough batch from flour weight and baker's percentages for home baking.
Result
985 g
500g flour at 75% hydration needs 375g water, 100g starter, and 10g salt, for 985g total dough
Quick Answer
A sourdough calculator treats flour as 100% and finds each other weight from that flour base. With 500 g flour, 75% water is 500 × 0.75 = 375 g. A 20% starter is 100 g, and 2% salt is 10 g. The full dough weight is 985 g.
How A Sourdough Calculator Uses Baker's Percentage
A sourdough calculator turns baker's percentages into ingredient weights. Flour stays at 100%. Water, starter, and salt are each set as a share of the flour weight. This lets you make a larger or smaller batch while the same ingredient proportions stay in place. King Arthur Baking uses this flour-first rule for baker's percentage. Enter the flour weight and the three percentages. The tool finds the water, starter, and salt, then adds all four weights. In this tool, hydration means the water percentage based on the flour you enter. The starter stays as one ingredient. Its flour and water are not split for the shown percentage. That keeps the tool useful for consistent recipe scaling. For full dough hydration, count the flour and water in the starter as well.
The Sourdough Formula For Water, Starter, And Salt
Baker's percentages define ingredient weights as a proportion of the total flour weight, which is always established as 100%.
- Ingredient weight = flour weight × (ingredient percentage ÷ 100).
- Total dough weight = flour + water + starter + salt.
Flour weight: the base weight, set as 100%.
Hydration: the water percentage based on flour weight.
Starter percentage: the starter weight based on flour weight.
Salt percentage: the salt weight based on flour weight.
Total dough: the sum of all four weights.
Using This Sourdough Calculator In Five Clear Steps
Inputs
- Flour weight: enter the flour amount in grams.
- Hydration: enter the hydration percentage based on flour weight.
- Starter: enter the starter percentage based on flour weight.
- Salt: enter the salt percentage based on flour weight.
Steps
- Choose the flour weight for your batch.
- Enter the hydration percentage from the bread formula.
- Add the starter and salt percentages.
- Find the water, starter, and salt weights.
- Check the full dough weight before you mix.
A Sourdough Recipe Example With Every Weight Shown
Flour weight is 500 g, water hydration is 75%, starter is 20%, and salt is 2%.
- Water weight = 500 × (75 ÷ 100) = 375 g.
- Starter weight = 500 × (20 ÷ 100) = 100 g.
- Salt weight = 500 × (2 ÷ 100) = 10 g.
- Total dough weight = 500 + 375 + 100 + 10 = 985 g.
Use 375 g water, 100 g starter, and 10 g salt with 500 g flour. The final batch weighs 985 g.
When Baker's Percentage Makes Recipe Scaling Clear
Use baker's math to adjust a bread formula, compare two bread mixes, or keep the same ratios in more than one batch. It also helps when a recipe gives percentages but leaves you to find the gram weights.
For other percentage, ratio, conversion, and culinary math tools, see the math calculators hub and look up concepts in the glossary.
Assumptions
- Flour is the 100% base for each percentage.
- Water, starter, and salt use the entered flour weight.
- All weights use the same unit.
- Starter is kept as one item.
- Total dough includes only the four listed items.
Limitations
- The tool does not split starter into flour and water.
- The shown hydration percentage is not full dough hydration when starter is used.
- Flour type, dough heat, and rise time are not found.
- Seeds, oil, sugar, and other add-ins are not part of the total.
- The result gives weights, not a forecast of how the loaf will bake.
In Practice
A common error is to use the full dough as the base. Baker's percentage uses flour as the base for every ingredient. Find water, starter, and salt from the flour weight, then add all four weights at the end.
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Sourdough Calculator Questions With Baking Answers
What Does Flour At One Hundred Percent Mean?
Flour is the fixed base in baker's math, so its weight is shown as 100%. All other weights are set against the flour. The percentages can add to more than 100% because they are not shares of the final dough.
How Is Sourdough Hydration Worked Out?
Hydration is water weight divided by flour weight, then times 100. In this tool, 375 / 500 × 100 = 75%. The shown hydration does not add the flour and water held in the starter.
Does Starter Change The Dough's True Hydration?
Starter changes full dough hydration because it holds both flour and water. This tool keeps starter as one item for quick scaling. For a full check, add starter water to all water and starter flour to all flour before you divide.
Can Baker's Percentage Scale A Recipe Up Or Down?
Baker's percentage keeps the same mix when the flour weight changes. Enter a new flour weight and keep the same water, starter, and salt percentages. The tool then gives the recalculated gram weights for the batch.
Sources
Last updated: . Reviewed for accuracy against the formula shown above.