Sourdough Hydration Calculator

Understanding the numbers

Baking sourdough is part art, part science and a little bit of maths. Use this sourdough hydration calculator to work out flour, water, starter and salt for one loaf.

Total flour weight

Enter the total flour you want in your recipe, including the flour inside your starter. This is not the weight of the finished loaf. Water, starter and salt affect dough weight, and the loaf loses moisture during baking.

Hydration

Hydration is total water as a percentage of total flour, including both in your starter. Higher hydration means wetter dough, which can be harder to handle. Around 70% is a useful starting point for a beginner wheat loaf; different flours absorb water differently.

Starter

Enter your starter weight in grams and its hydration. A starter fed equal weights of flour and water is 100% hydration. For example, 100g of this starter contains 50g flour and 50g water. The calculator subtracts these from the flour and water you need to add.

For a recipe with 500g total flour, 100g starter is 20% of the total flour weight. Fermentation speed also depends on temperature and starter activity, so watch the dough as well as the clock.

Salt

Salt is calculated as a percentage of total flour. A typical starting point is 2%.

A worked example

With 500g total flour, 75% hydration, 100g starter at 100% hydration and 2% salt, add 450g flour, 325g water, 100g starter and 10g salt. This makes 885g of dough before baking.

Ready to bake?

Follow our beginner sourdough recipe for the full method. Need a culture? Choose a live sourdough starter or compare live and dehydrated starters. Find bread flour for your next loaf.

goodbye guesswork

Dough My God Baker's Calculator

Calculate exactly how much flour, water, starter and salt to add or work out what hydration your dough is.

A practical starting point

Flour 500 g
Hydration 70%
Starter 20%
Salt 2%
Total dough 860 g

Sourdough Calculator

Build a recipe or check one you already have

Build a sourdough recipe below or check your hydration. Choose how much flour in total you would like in your loaf. (Eg: 500g is a regular sized loaf, 750g large and 1000g very large0. Next, choose hydration, amount of starter and salt and the calculator will take care of the rest. 

Inputs

Around 500 g makes a standard loaf. Around 1,000 g makes one very large loaf or two standard loaves.
20% starter is a practical starting point.
A starter fed equal weights of flour and water is 100% hydration.
2% salt is a good place to start.

What to add

  • Flour0 g
  • Water0 g
  • Salt0 g
Copied!

Totals

  • Flour (total)0 g
  • Water (total)0 g
  • Salt0 g
  • Starter0 g
  • Starter percentage0%
Dough total: 0 g

Understand the numbers

How the calculator works

Sourdough is part art, part science and a little maths. These are the numbers behind the dough.

Total flour weight

Total flour is the total weight of flour in your recipe and includes the flour in your starter. 500 g makes a standard sized loaf and  1,000 g makes one very large loaf or two standard loaves.

Hydration

Hydration is total water as a percentage of total flour, including both inside your starter. A 70% hydration is a practical starting point for a beginner wheat loaf.

Starter

Enter the starter weight and its hydration. A starter fed equal weights of flour and water is 100% hydration. Using starter equal to 20% of the total flour is a practical starting point.

Salt

Salt is calculated as a percentage of total flour. A 2% salt level is a good place to start.

A worked example

With 500 g total flour, 70% hydration, 100 g starter at 100% hydration and 2% salt, add 450 g flour, 300 g water, 100 g starter and 10 g salt. This makes 860 g of dough before baking.

Ready to bake?

Use the calculated weights in our beginner sourdough recipe, or choose a live starter to begin.

Beginner recipe Choose a starter