Sourdough Calculator
Free Sourdough Calculator for desserts & baking recipes. Enter amounts to convert, scale, or adjust ingredients precisely.
Formula
Flour = Total Dough / (1 + Hydration + Salt%)
Total flour weight is derived by dividing the desired total dough weight by the sum of all baker's percentages (1 for flour + hydration decimal + salt decimal). The starter's flour and water contributions are then subtracted from the totals to determine added flour and added water amounts. Starter flour fraction = 1/(1 + starter hydration).
Worked Examples
Example 1: Standard Sourdough Loaf (1 kg dough)
Problem: Calculate ingredients for a 1000g dough at 75% hydration, 20% starter (100% hydration), and 2% salt.
Solution: Total flour = 1000 / (1 + 0.75 + 0.02) = 1000 / 1.77 = 564.97g\nStarter = 20% x 565.0 = 113.0g (56.5g flour + 56.5g water)\nAdded flour = 565.0 - 56.5 = 508.5g\nTotal water = 75% x 565.0 = 423.7g\nAdded water = 423.7 - 56.5 = 367.3g\nSalt = 2% x 565.0 = 11.3g\nTotal: 508.5 + 367.3 + 113.0 + 11.3 = 1000.0g
Result: Flour: 508.5g | Water: 367.3g | Starter: 113.0g | Salt: 11.3g
Example 2: High-Hydration Ciabatta Sourdough
Problem: Calculate ingredients for 750g dough at 85% hydration, 15% starter (100% hydration), 1.8% salt.
Solution: Total flour = 750 / (1 + 0.85 + 0.018) = 750 / 1.868 = 401.5g\nStarter = 15% x 401.5 = 60.2g (30.1g flour + 30.1g water)\nAdded flour = 401.5 - 30.1 = 371.4g\nTotal water = 85% x 401.5 = 341.3g\nAdded water = 341.3 - 30.1 = 311.2g\nSalt = 1.8% x 401.5 = 7.2g
Result: Flour: 371.4g | Water: 311.2g | Starter: 60.2g | Salt: 7.2g
Frequently Asked Questions
What is baker's percentage and why is it used for sourdough recipes?
Baker's percentage (also called baker's math) is a system where every ingredient is expressed as a percentage of the total flour weight, with flour always being 100%. For example, 75% hydration means the water weight is 75% of the flour weight, and 20% starter means the starter weighs 20% of the flour. This system is universally used in professional baking because it makes recipes infinitely scalable — you can make one loaf or one hundred using the same percentages. It also makes it easy to compare recipes and understand dough characteristics at a glance. A 65% hydration dough will be noticeably stiffer than an 80% hydration dough, regardless of total batch size. Baker's percentage accounts for the flour and water contributed by the sourdough starter itself.
How does hydration percentage affect sourdough bread?
Hydration dramatically affects the texture, crumb structure, and handling properties of sourdough bread. Lower hydration doughs (60-65%) produce tighter, more uniform crumbs suitable for sandwich bread and are easier to shape. Medium hydration (68-75%) creates a balance of open crumb and workability, ideal for most artisan loaves. High hydration (78-85%) yields the large, irregular holes characteristic of ciabatta and high-hydration country loaves but requires advanced shaping skills. Very high hydration (85%+) produces focaccia-style breads. Higher hydration also extends fermentation time slightly and increases oven spring. Beginners should start at 70-72% and gradually increase as they develop handling skills, since wet doughs are more challenging to shape and score.
What is the ideal sourdough starter percentage and how does it affect fermentation?
The starter percentage controls fermentation speed and flavor development. A lower percentage (10-15%) creates a longer, slower fermentation that develops more complex sour flavors through increased lactic and acetic acid production. A higher percentage (25-30%) speeds up fermentation significantly, producing a milder, sweeter bread. The standard range of 15-20% balances flavor development with practical timing, typically allowing a 4-6 hour bulk fermentation at room temperature. In cold weather, increasing to 25% compensates for slower yeast activity. In hot weather, reducing to 10-12% prevents over-fermentation. The starter should be used at its peak activity — typically 4-8 hours after feeding when it has doubled in volume and shows a domed top with bubbles throughout.
How much salt should I use in sourdough bread and does it affect fermentation?
The standard salt percentage for sourdough bread is 1.8-2.2% of total flour weight, with 2% being the most common recommendation. Salt serves multiple critical functions: it strengthens gluten structure, controls fermentation rate, enhances flavor, and improves crust color through better caramelization. Reducing salt below 1.5% produces bland bread that ferments too quickly and has a weaker crumb structure. Exceeding 2.5% can inhibit yeast activity excessively and make bread taste overly salty. Fine sea salt or kosher salt dissolves most easily into dough. Many bakers add salt during the autolyse or after initial mixing, as adding it too early can tighten the gluten prematurely and inhibit initial hydration. Salt should never be mixed directly with the starter, as high salt concentration can kill the wild yeast.
How do I get the most accurate result?
Enter values as precisely as possible using the correct units for each field. Check that you have selected the right unit (e.g. kilograms vs pounds, meters vs feet) before calculating. Rounding inputs early can reduce output precision.
Does Sourdough Calculator work offline?
Once the page is loaded, the calculation logic runs entirely in your browser. If you have already opened the page, most calculators will continue to work even if your internet connection is lost, since no server requests are needed for computation.