Sourdough Hydration, Really Explained

Hydration determines more about your bread than any other single variable. It controls crumb structure, crust texture, ease of handling, fermentation speed, and oven spring. Understanding what the numbers mean — and what they feel like in the bowl — is the difference between following recipes and actually knowing what you are doing.

Hydration is just one number

Hydration = total water weight ÷ total flour weight, expressed as a percentage. 500g flour + 375g water = 75% hydration. The hydration calculator does this math including the flour and water inside your starter, which matters more than most bakers realize.

The range, low to extreme

50–58% — bagel and pretzel territory. Stiff, dense dough that holds its shape through boiling. Feels like modeling clay.

58–65% — pan breads, sandwich loaves, enriched doughs. Clean to handle, tight crumb that slices without tearing.

65–70% — the beginner-friendly artisan sweet spot. Shapeable with basic technique, produces recognizable sourdough character.

70–75% — classic artisan loaf. Open crumb starts appearing. 72% is arguably the most common home sourdough target.

75–80% — high-hydration territory. Beautiful open crumb, dramatic ears, but demands confident shaping. This is where bench scrapers become essential.

80–85% — ciabatta and focaccia. The dough is essentially a wet batter that gets poured more than shaped.

85%+ — specialty territory for experienced bakers. Cold retard is almost mandatory to get any structure.

What hydration does to the bread

Higher hydration produces more steam inside the loaf during baking, which opens the crumb and creates larger, more irregular holes. Gluten stretches further, allowing bigger rise. The crust comes out thinner and crispier. Fermentation moves faster because enzymes are more active in wetter environments.

Lower hydration produces a tighter, more uniform crumb. The crust is thicker and chewier. Shaping is easier and more precise. Fermentation is slightly slower, and the bread slices cleanly without tearing. Neither direction is “better” — they produce different breads.

Why your dough feels different at the same hydration

Flour protein. King Arthur bread flour at 12.7% protein absorbs significantly more water than a generic all-purpose at 10.5%. The same 75% hydration dough feels dramatically different with each flour.

Flour type. Whole wheat absorbs roughly 10% more water than white flour. A 75% hydration whole wheat dough handles like a 65% white dough. Rye absorbs differently still — it holds water in pentosans rather than gluten, producing a sticky texture that is normal and not a sign of over-hydration.

Temperature. Warm dough (80°F+) feels slacker and more extensible than the same dough at 65°F. The water content has not changed; the gluten behavior has.

How to increase hydration gradually

If you are comfortable at 70%, do not jump to 78%. Move in 2–3% steps. Bake at 72% until it feels routine. Then 74%. Then 76%. Each step teaches you what that hydration feels like in your hands, with your flour, in your kitchen. The lessons compound — literally and figuratively.

Technique matters more than numbers

Above 75%, technique is what makes the bread work. Three techniques that unlock high-hydration baking:

Bassinage. Hold back 5–10% of the water during initial mixing. Add it in stages after gluten has begun developing. The dough absorbs more water once gluten is established.

Coil folds. During bulk fermentation, slide your hands under the dough and lift from the center, letting the sides fold underneath. Builds tension without deflating the gas structure. More effective than stretch-and-fold at high hydrations.

Cold retard. 8–36 hours in the fridge after shaping. Firms the dough for cleaner scoring, slows acid production for better flavor balance. The timeline generator can help plan around an overnight retard.

What hydration tells you about a recipe

Before baking an unfamiliar recipe, calculate its hydration with the hydration calculator. That single number tells you how tricky handling will be, what crumb to expect, whether you need a banneton, and how much technique you will need. A 65% recipe is straightforward. An 80% recipe needs bench scraper work and wet hands. A 90% recipe probably needs a loaf pan.

The myth of “higher hydration is better”

Instagram rewards open crumb and dramatic ears, which come from high hydration. But higher hydration produces a specific bread, not a universally better one. A 72% sandwich loaf that slices perfectly is not inferior to an 82% ciabatta with massive holes. Pick hydration for the bread you want to eat, not the photo you want to post.