Bread Hydration Calculator

Hydration — water as a percentage of flour — is the single number that most changes how a dough handles and how open the crumb bakes. Enter flour and water to see where a recipe sits, or enter flour and a target percentage to get the water to add.

If a sourdough starter is involved, add its weight and hydration and the calculator folds its flour and water into the true totals. Results are classified as stiff (under 60%), standard (60–75%), or high hydration (over 75%).

Common uses

• Check a recipe's real hydration before committing to it
• Work out water for 500 g of flour at 70% without mental math
• See how much a 100 g starter shifts a small dough's hydration

Example

500 g flour · 340 g water

68% hydration — standard dough

What is bread hydration percentage?

Water weight divided by flour weight, times 100. A dough with 500 g flour and 340 g water is at 68% hydration — the number that most determines how sticky the dough feels and how open the crumb bakes.

What counts as high hydration dough?

This calculator classifies anything over 75% as high hydration, 60 to 75% as standard, and under 60% as stiff. High-hydration doughs bake an open crumb but are sticky to handle; stiff doughs suit bagels and pretzels.

Does sourdough starter count toward hydration?

Yes. A 100%-hydration starter is half flour and half water, and the calculator folds both halves into the totals — so 100 g of starter adds 50 g to your flour total and 50 g to your water total before the percentage is computed.

How much water do I need for 500 g of flour at 70%?

350 g, since water is flour weight times the hydration percentage. If a starter is in the mix, the calculator first credits the starter's water and flour, then tells you how much water is left to add.

Does the hydration calculator upload my numbers anywhere?

No. The percentage is computed in your browser as you type; nothing is transmitted to a server or kept afterward.