How to use the sourdough hydration calculator
- Choose Check my dough’s hydration to analyse a recipe, or Water for a target hydration to plan one.
- Enter the flour and water you add to the dough (not counting the starter).
- Enter how much starter you use and its hydration (100% if you feed equal weights of flour and water).
- Add the salt to see it as a percentage of total flour.
Sourdough hydration formula
Starter flour = Starter ÷ (1 + starter hydration) Starter water = Starter − starter flour Total flour = Flour + starter flour Total water = Water + starter water Hydration % = Total water ÷ Total flour × 100 Water needed for a target = Target % × Total flour − starter water
Worked example
500 g flour, 350 g water, 100 g starter at 100% hydration and 10 g salt:
- Starter = 50 g flour + 50 g water
- Total flour = 550 g; total water = 400 g
- Hydration = 400 ÷ 550 = 72.7% (not 70% as it first appears)
- Salt = 10 ÷ 550 = 1.8%
To make the same dough at 75%, you need 0.75 × 550 − 50 = 362.5 g of water.
Hydration guide
| Hydration | Dough feel | Good for |
|---|---|---|
| 55–62% | Stiff, easy to shape | Bagels, pretzels, sandwich bread |
| 63–68% | Firm but supple | Beginner loaves, tin loaves, rolls |
| 69–75% | Soft, slightly sticky | Classic country sourdough |
| 76–82% | Wet, needs folds | Open-crumb boules and batards |
| 83%+ | Very wet, hard to shape | Ciabatta, focaccia, pan pizza |
Baker’s percentages
Bakers write every ingredient as a percentage of the flour weight, with flour = 100%. A typical sourdough might be flour 100%, water 70%, starter 20%, salt 2%. Using percentages makes it easy to scale a recipe up or down: for 1 kg of flour you need 700 g water, 200 g starter and 20 g salt.
Adapting a recipe to your flour
Flour absorbs different amounts of water depending on its protein, how finely it is milled and how much bran it contains. A recipe written for strong Canadian or North American bread flour at 75% may feel soupy with a softer all-purpose flour or Indian maida. Start 3–5 percentage points lower than the recipe, then add the remaining water during mixing if the dough can take it. Note the hydration that works with your flour, and use the target mode of this calculator to plan future bakes.
Tips for handling high-hydration dough
- Hold back 5–10% of the water and add it after mixing (bassinage) to build strength first.
- Use stretch and folds during bulk fermentation instead of kneading.
- Wet your hands, not the bench, when handling sticky dough.
- Choose strong bread flour (12–14% protein) for 75%+ hydration.
- Temperature matters: warm dough feels wetter and ferments faster; aim for 24–26 °C (75–78 °F).