What hydration really changes
2 April 2026
Hydration is the weight of water divided by the weight of flour. A 70% dough has 700 g of water per kilo of flour. The number is easy to calculate and easy to misread.
Higher hydration gives a more open crumb and a thinner crust, but only if the flour can hold the water. The same 78% that works with a strong bread flour turns a soft all-purpose flour into soup.
My rule: start at 68%, bake the same recipe three times, and raise the water by 2% each time. Stop when shaping becomes a fight. For the flour I buy, that point is 74%.
Wholemeal absorbs more. When I swap in 20% wholemeal I add roughly 3% extra water and the dough feels the same in the hand.