Sourdough Hydration Explained: What Percentage Should You Actually Use?
Hydration is the number that decides how your dough feels in your hands, how open the crumb turns out, and how likely you are to end up scraping a sticky mess off the counter. It is also the number most bakers copy from a recipe without ever asking whether it suits their flour, their kitchen, or their skill level. It should.
Here is the definition in one line: hydration is the weight of the water divided by the weight of the flour, expressed as a percentage. 750 g of water against 1000 g of flour is a 75% hydration dough. That is the whole calculation. If the percentage system itself is new to you, start with what baker’s percentage is and come back.
What the percentage actually controls
Water is not a passive ingredient. Adding more of it changes the physics of the dough in three ways at once, which is why the same recipe at 68% and 80% produces two genuinely different breads.
It changes how freely the dough moves. Gluten needs water to become extensible. A wetter dough stretches further before it tears, flows rather than holds, and spreads outward when you set it down. A drier dough resists, holds a shape, and stays where you put it.
It changes the crumb. More water means gas bubbles can expand more easily against a softer, more mobile matrix, so the crumb opens up into the large irregular holes people chase in photographs. Less water means a tighter, more even, more sandwich-like crumb. Neither is a defect. They are different breads.
It changes fermentation speed. Enzymes and microbes work in solution, so a wetter dough ferments measurably faster at the same temperature. Push hydration up and your bulk window shortens, which catches people out when they raise hydration and keep the old timings.
The practical ranges
These are working bands rather than hard boundaries, and they assume a standard white bread flour.
| Hydration | How it handles | Crumb | Best for |
|---|---|---|---|
| 60–65% | Firm, holds shape, easy to shape tightly | Tight and even | Sandwich loaves, beginners, enriched doughs |
| 68–72% | Soft but cooperative, still shapeable | Moderately open | Your first real sourdough boule |
| 73–78% | Slack and tacky, needs confident handling | Open, irregular | The everyday artisan sourdough range |
| 80–85% | Flows, sticks, wants a bench scraper | Very open, glossy | Ciabatta-style, experienced hands |
| 85%+ | Barely a dough, more of a batter | Dramatic, wild | Focaccia, specialists, and stubborn people |
If you are new to sourdough, start at 70%. It is high enough to give you a genuinely open crumb and low enough that the dough still behaves. Bakers who begin at 85% because the internet told them to usually spend three months making flat loaves and blaming their starter.
The number on the recipe is not the number in your bowl
This is the part that trips up almost everyone who raises hydration and gets a soup, and it comes down to two facts.
Your flour has its own opinion. Flours absorb wildly different amounts of water. Whole wheat and rye carry bran and germ, which soak up far more water than refined white flour does. Higher-protein bread flour absorbs more than a soft all-purpose. This means 80% hydration in strong whole wheat can feel firmer than 72% in a weak white flour. Copying a percentage from a recipe written for a different flour is copying the wrong number. Adjust to how the dough feels, and treat the percentage as a record of what you did rather than a rule you obey.
Your starter is carrying water too. A 100% hydration starter is half flour and half water by weight, and both halves end up in your dough. Include 200 g of it in a 1000 g flour recipe and you have quietly added 100 g of flour and 100 g of water that the headline percentage never mentioned. Your true hydration is always a little higher than your formula hydration. It is a small gap, but it is exactly the gap that makes a “75%” dough feel wetter than you expected, and it is the calculation the Hydration Calculator runs for you automatically.
How to raise hydration without wrecking a bake
Wetter dough is not harder because of the water alone. It is harder because wet dough punishes weak technique. Move up in steps and give yourself the tools.
Go up 3 to 5 points at a time. Bake the same formula twice at 72% before you try 76%. Jumping ten points in one go changes handling, timing, and shaping all at once, so when it fails you learn nothing about which one broke.
Build more strength, not more flour. The instinct when dough feels slack is to dust in extra flour, which silently lowers your hydration and teaches you nothing. Use an extra set of stretch and folds instead, or extend the autolyse so the flour is fully hydrated before you judge it.
Wet your hands, not the bench. Water on your hands stops sticking without changing the formula. Flour on the bench changes the formula.
Shorten your bulk. Remember that the same dough ferments faster when wetter. If you raise hydration and keep the old bulk time, you are not fighting the water, you are fighting an overproofed dough. The real end point is in the visual signs your dough is ready, never the clock.
Fix the temperature before blaming the water. A slack, unmanageable dough at 78% in a 29°C kitchen is usually an overfermented dough, not an overhydrated one. Cool the dough and the same hydration suddenly behaves.
Choose the number for the bread you want
There is no correct hydration, only the hydration that matches the loaf you are trying to make and the flour in front of you. Want tidy slices for toast and sandwiches? Sit at 65% and stop apologizing for it. Want the open, glossy, irregular crumb? Work your way up to the high seventies with strong flour and a well-developed dough.
Decide what you want the bread to be, pick the band that produces it, then hold that number steady across a few bakes so you can actually read what changed. The Hydration Calculator does the arithmetic in both directions, giving you the water for a target percentage or the percentage from what you already mixed, including the water hiding in your starter.
Get the number deliberate rather than inherited, and hydration stops being the thing that ruins your loaves and becomes the dial you use to shape them.