BakersMath Sourdough Calculator
Calculate baker's percentages, isolate levain water/flour fractions, and scale sourdough bread recipes accurately.
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Includes flour and water contributed by sourdough starter levain.
All ingredients expressed as a percentage of total flour weight.
Scale total batch weight or target loaf weight instantly.
Understanding Baker's Percentages
In professional baking, formulas are expressed using Baker's Percentages. Unlike standard percentages where all ingredients sum to 100%, in baker's math, total flour weight is always defined as 100%. Every other ingredient (water, salt, levain, inclusions) is measured relative to total flour weight.
How True Sourdough Hydration is Calculated
A common mistake in sourdough baking is calculating hydration based only on the added water and flour, ignoring the flour and water present inside the active starter (levain).
Our calculator isolates the starter's hydration (typically 100%, meaning equal parts flour and water) and incorporates those fractions into the overall formula:
Total Flour = Main Flour + Levain FlourTotal Water = Main Water + Levain WaterTrue Hydration % = (Total Water / Total Flour) × 100
Sample Sourdough Formula (75% Hydration)
- Total Flour: 500g (100%)
- Total Water: 375g (75%)
- Active Starter (100% hydration): 100g (20% → 50g flour + 50g water)
- Salt: 10g (2%)
- Main Flour Added: 450g
- Main Water Added: 325g
Scaling Recipes for Any Loaf Size
Adjust the desired number of loaves or target individual dough ball weight, and our tool re-calculates all ingredient weights in grams instantly.
Frequently Asked Questions
Why does sourdough starter hydration matter when calculating bread recipes?
A 100% hydration sourdough starter contributes equal parts flour and water to the total dough formula. Ignoring levain weights results in dough that is significantly wetter or drier than intended.
How do I scale a single loaf sourdough recipe to 4 loaves?
Enter 4 in the target loaf count input. The calculator scales the total flour baseline and recomputes all ingredient weights in grams instantly.
What is a typical salt percentage in artisan sourdough?
Standard baker's percentage for salt is between 1.8% and 2.2% of total flour weight. 2.0% (10g salt per 500g total flour) is the industry standard baseline.