Sourdough bread calculator
A classic country loaf at 75% hydration with 10% whole wheat and 20% levain. Change any percentage, the number of loaves or their weight, and the grams update — with the levain's flour and water already counted.
Formula baker's % of total flour
Batch size
Preferment
Water temperature
Use water at 92°F
78 × 4 − (70 + 72 + 2 + 76) = 92
Your recipe
| Ingredient | Baker's % | Total formula | Mix |
|---|---|---|---|
| Bread flour | 90% | 915 g | 814 g |
| Whole wheat flour | 10% | 102 g | 102 g |
| Water | 75% | 763 g | 661 g |
| Salt | 2% | 20 g | 20 g |
| Sourdough levain 100% hydration | 20% | — | 203 g |
| Total | 177% | 1,800 g | 1,800 g |
Build the levain
4–12 hours before mixing, combine 41 g ripe starter (100% hydration), 81 g bread flour and 81 g water (≈ 1 : 2 : 2). Use it at its peak: domed, bubbly, about doubled.
Sourdough bread formula at a glance
Yield 2 loaves · 1,800 g dough · 75% hydration · about 24 hours start to finish.
| Ingredient | Baker's % |
|---|---|
| Bread flour | 90% |
| Whole wheat flour | 10% |
| Water | 75% |
| Salt | 2% |
| Sourdough levain (prefermented flour) | 10% |
Building the levain? The starter feeding calculator gives grams for 1 : 1 : 1 to 1 : 10 : 10 and the time to peak.
Why these percentages
In this calculator every percentage refers to the total flour in the recipe, including the flour inside the levain. That is how professional bakers write formulas and it is why "75% hydration" here means exactly what it says: all the water divided by all the flour. Calculators that ignore the starter under-report hydration by several points, which is why a recipe can feel much wetter than its label.
With 20% levain at 100% hydration, 10% of the flour is prefermented. That is a moderate inoculation that gives a 4–5 hour bulk at 78°F. In a warm kitchen drop the levain to 10–15%; in a cold one raise it to 25% or warm the water using the dough temperature section — temperature changes fermentation speed far more than small changes in levain.
New to the formula? Start at 70–72% hydration until shaping feels comfortable, then move up in 2-point steps. Whole wheat absorbs more water, so if you raise it to 30% or more, add 3–5% water as well.
Method
- Build the levain. Mix ripe starter, flour and water as shown in the levain build and leave it 4–12 hours until domed, bubbly and roughly doubled.
- Mix. Combine the flours with most of the water and rest 30–60 minutes (autolyse). Add the levain, salt and the rest of the water and squeeze until fully combined.
- Bulk ferment. Keep the dough near 78°F (25–26°C). Do 4 sets of stretch-and-folds in the first 2 hours, then leave it until it has grown 50–75%, is domed and jiggly — usually 4–5 hours.
- Shape. Divide, pre-shape into loose rounds, rest 20–30 minutes, then shape into tight boules or batards and place seam-side up in floured bannetons.
- Cold proof. Cover and refrigerate 12–16 hours at 38–40°F (3–4°C). The cold firms the dough, deepens flavor and makes scoring easier.
- Bake. Bake straight from the fridge in a preheated Dutch oven at 500°F (260°C) with the lid on for 20 minutes, then uncovered at 450°F (230°C) for 20–25 minutes until deep brown and 205–210°F (96–99°C) inside.
Tips
- Total hydration includes the levain's water
- 2% salt of total flour is standard
- Bulk until 50–75% risen, not a fixed time
- Hold back 5% of the water and add it with the salt
Want the reasoning behind the numbers? See baker's percentages explained and the bread hydration chart.
FAQ
Does sourdough hydration include the starter?
Yes. True hydration is all the water (including the water in the levain) divided by all the flour (including the flour in the levain). 450 g flour, 325 g water and 100 g starter at 100% hydration is 375 ÷ 500 = 75%.
How much levain should I use?
15–25% of total flour by weight (7.5–12.5% prefermented flour at 100% hydration) suits most kitchens. Use less when it is warm or you want a longer bulk, more when it is cold.
How much dough do I need for one loaf?
About 900 g of dough makes a loaf for a standard 9–10 inch (23–25 cm) banneton or a 5 qt Dutch oven; 750 g suits an 8 inch banneton.