Precision Sourdough Calculator & Baker’s Percentages

Baker's math is a standardized ratio system used by bakers worldwide to scale recipes up or down effortlessly without altering the final bread characteristics. By expressing each ingredient as a percentage of the total flour weight (always 100%), you can easily bake one 500g loaf or fifty 1kg loaves with identical dough hydration, texture, and flavor.

In baker's percentages, total flour is always established as the 100% baseline. Every other ingredient is calculated as a mathematical percentage of that total flour weight. Because water (e.g., 72%), starter (20%), and salt (2%) are added on top of the 100% flour base, the total recipe percentage will add up to 194% (or more), representing the total dough yield.

Select your calculation mode (By Loaf Weight or By Flour Weight), enter your batch size (number of loaves and target loaf weight), and adjust your baker's percentages for hydration (water), starter (levain), and salt using the interactive sliders or steppers. You can also customize your multi-flour blend (Bread, Whole Wheat, Rye, Spelt) and optional add-ins (olive oil, honey, seeds). The calculator instantly computes exact gram weights and true total hydration in real time.

Yes! Our sourdough calculator computes both Baker's Formula Hydration (water relative to base flour) and True Total Hydration. Assuming a standard 100% hydration starter (equal parts flour and water), 100g of starter contributes 50g of flour and 50g of water. The calculator automatically incorporates these into the true hydration breakdown.

Most artisan sourdough recipes use between 15% and 20% active starter (levain) relative to total flour weight (e.g., 75g to 100g of starter per 500g of flour). In warm environments (26°C–28°C / 78°F–82°F) or for slow overnight ferments, reduce starter to 10%–15% to prevent over-fermentation. In cool kitchens (18°C–21°C / 64°F–70°F), increase starter to 20%–25% to speed up bulk rise.

Hydration is the ratio of total water weight to total flour weight expressed as a percentage. For example, mixing 350g of water with 500g of flour yields 70% hydration (350 ÷ 500 × 100). Higher hydration produces a more open, airy crumb with custard-like texture, but requires greater dough handling skill.

For beginners, an ideal hydration level is 65% to 70% (e.g., 68% hydration using strong white bread flour). At 68%–70%, the dough develops excellent gluten structure, remains easy to knead and shape into a tight boule, and will not slacken or stick excessively to your hands or banneton.

Salt plays three vital roles: flavor seasoning, gluten tightening, and yeast regulation. Salt strengthens gluten bonds and slows down enzymatic breakdown. Below 1.8%, bread tastes bland and dough can become loose and sticky. Above 2.2%, salt excessively retards wild yeast activity and creates an overly salty crust. 2.0% is the universal gold standard.

A starter (or 'mother') is the ongoing, continuously maintained culture of wild yeast and lactic acid bacteria kept in your fridge or kitchen counter. A levain (or 'off-shoot build') is a specific portion of mature starter fed with fresh flour and water at an exact ratio (e.g., 1:2:2) to reach peak volume and activity right when you mix your bread dough.

Feeding ratios represent [Starter Weight] : [Flour Weight] : [Water Weight]. A 1:1:1 ratio (e.g., 20g starter + 20g flour + 20g water) peaks quickly in 3 to 4 hours. A 1:2:2 ratio (20g starter + 40g flour + 40g water) provides more food and peaks in 5 to 6 hours. A 1:5:5 ratio (10g starter + 50g flour + 50g water) takes 8 to 12 hours to peak, making it ideal for overnight levain builds.

Overly sticky, tearing dough is usually caused by either: (1) Over-fermentation, where microbial acids break down the gluten protein network into soup; (2) Weak flour protein that cannot absorb your target hydration; or (3) Underdeveloped gluten from insufficient stretch-and-fold cycles or excessive dough temperature.

A dense, gummy crumb (often with a heavy streak along the bottom crust) is most commonly caused by under-fermentation (cutting bulk fermentation too short), baking at too low a temperature, cutting into the loaf while still hot before starches set (always wait at least 2 hours!), or insufficient bottom heat in the Dutch oven.