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Dough hydration: what the percentage means and how to steer it

By BakePen Editorial · Last updated 22 Sep 2026 · 5 min read

Two loaves can share flour, yeast, salt and schedule and behave like different species, because one is at 62% hydration and the other at 78%. Hydration — total water as a percentage of total flour — is the strongest single predictor of how a dough mixes, handles, shapes and finally eats. It is also the figure home bakers most often compute wrongly, by leaving their starter out of it.

This article explains what the number governs, the ranges where familiar breads live, how flour type moves the target, and how to adjust a dough that has landed too wet or too dry — in the bowl, not just on paper.

What hydration actually controls

Water hydrates flour's proteins so they can form gluten, dissolves salt and yeast so they distribute, and sets the dough's consistency. A drier dough is firm, holds a shape, and traps gas in small, even cells — sandwich crumb. A wetter dough flows, stretches under its own weight, and lets gas gather in the large, irregular holes of a rustic loaf. Neither is better; they are different breads that happen to share a flour bag.

Hydration also flavours time. Wetter doughs ferment a little faster and develop flavour compounds more freely; drier doughs are slower and sturdier. When a recipe's schedule feels wrong, its hydration, interacting with your kitchen's temperature, is usually the reason.

The ranges, honestly labelled

Bagels and pretzels live at 50–58%: stiff doughs that must be rolled and shaped firmly. Standard sandwich and tin loaves sit at 58–65%. Everyday home loaves and pizza doughs occupy 65–72%. Rustic, open-crumb styles — ciabatta, focaccia, many sourdoughs — run 72–85%, with focaccia happily wetter still because the tin does the shaping. Beyond 85% you are making a batter with ambitions, and special handling is the recipe, not an adjustment.

These are ranges, not commandments, because flour moves them. Strong bread flour absorbs more water than soft; wholemeal more than white, thanks to the bran; a freshly milled flour drinks differently from an aged one. The same 70% can be supple with one bag and slack with another — which is why bakers speak of hydration as a starting point and dough feel as the verdict.

Counting honestly: the starter problem

A sourdough starter is flour and water in a known ratio, and both halves belong in the hydration sum. A dough of 500 g flour and 320 g water plus 100 g of starter at 100% hydration is not a 64% dough: it is 370 g of water over 550 g of flour — 67.3%. The three-point gap is small on paper and obvious in the hands, and it explains a shelf of 'the recipe lied' loaves that were, in fact, mis-added.

The hydration calculator exists for exactly this sum, including starters kept wetter or drier than 100%. If you maintain a stiff starter at 60%, its water share shrinks accordingly — the tool takes the figure you feed your starter at, which is the only honest way to count it.

Adjusting a dough in the bowl

Too dry announces itself early: the dough tears rather than stretches, resists the hook, and the bowl never quite cleans. Add water a tablespoon at a time — 15 g on a 500 g flour dough is one hydration point — and give each addition two minutes to absorb before judging. Doughs drink slowly and forgive slowly.

Too wet is the harder rescue, because adding flour unbalances salt and yeast slightly and changes the bread's size. Work it first: time, folding and the dough's own gluten development tighten a slack dough more than beginners expect. If flour must go in, add it in small dustings during folds, accept a marginally bigger loaf, and note the corrected hydration for next time. The dough you rescue teaches the formula you keep.

Hydration ranges by style

From 64% on paper to 67% in the hands

A baker follows a sourdough formula: 500 g flour, 320 g water, 100 g starter, 10 g salt. The page she found it on calls it 64% hydration — water over flour, starter ignored. Her dough feels nothing like the video's 64%: it spreads between folds and sticks to everything. Counted properly — 370 g water, 550 g flour — it is 67.3%, a different handling class. Nothing was wrong with her flour or her folding; the label was wrong, and with the right number the dough's behaviour makes sense, and so do the adjustments.

Common mistakes

Adding water all at once to fix a dry dough. A flood of water sits on the dough’s surface and turns mixing into splashing. Tablespoon additions, absorbed fully between each, keep control.

Judging hydration in the first two minutes. Freshly mixed dough always feels rougher and drier than it will after a rest. Autolyse — even twenty minutes — changes the verdict; adjust after it, not before.

Chasing a number your flour disagrees with. A soft flour at 78% is soup; the same number with strong flour is a delight. If the dough says no three bakes running, the flour has voted — lower the target.

Questions, answered

Does oil or egg count toward hydration?

Strictly, hydration is water. Eggs are about three-quarters water and many bakers count their water share in enriched doughs; oil does not hydrate flour at all, though it softens the crumb.

Why is my wholemeal dough thirstier at the same percentage?

Bran absorbs water slowly and holds more of it. Wholemeal doughs often want 3–6 points more hydration than white, and the water is best added with a rest so the bran can take it up.

Can high hydration fix a weak flour?

No — it exposes it. Weak flour at high hydration spreads and tears. Match hydration to the flour’s strength and let time and folds build what protein the flour has.

The short version

Hydration is the dial that turns one flour into many breads. Learn its ranges, count your starter honestly, adjust in small honest steps, and the number stops being trivia from forums and becomes what it is for working bakers: the first thing you decide, and the thing you change when a loaf needs to become a different loaf.

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