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Sourdough Hydration Calculator
Compute your sourdough dough's hydration as baker's percentage from flour, water, and starter weights, and see recommended water to add for a target hydration level.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
Assumes a 100% hydration (equal parts flour and water) starter.
Current hydration
0%
Water to add/remove for target
0 g
Example shown — replace it with your own dough's weights.
How it works
- Enter your flour, water, and starter weights in grams.
- The starter's flour and water content (assuming 100% hydration) is added to your totals.
- Current hydration is shown as a percentage, plus how much water to add or remove to hit your target.
FAQ
What is baker's percentage hydration?
It's the total water weight expressed as a percentage of total flour weight (water ÷ flour × 100). A 75% hydration dough has 75g of water for every 100g of flour — it's the standard way bakers compare dough wetness across recipes of any size.
Why does the starter count toward flour and water?
A sourdough starter is itself flour and water fermented together. Ignoring it undercounts your true hydration, especially in recipes with a large percentage of starter — this calculator assumes a typical 100% hydration starter (equal parts flour and water) and folds its contribution in.
What hydration should I target as a beginner?
Around 65-70% is a forgiving, easier-to-handle range for beginners. Higher hydration (75%+) gives a more open crumb and chewier crust but is stickier and harder to shape — work up to it as your technique improves.
Calculator vs. weighing by feel
| Feature | This calculator | Eyeballing dough consistency |
|---|---|---|
| Repeatable results recipe to recipe | ✓ | ✗ |
| Adjusts instantly for flour's actual absorption | ✗ | ✓ |
Use this to hit a consistent target hydration on paper, then adjust slightly by feel since flour absorption varies by brand and humidity.