Sourdough Calculator

Choose your loaf size, quantity and dough style to get an easy sourdough recipe with the right amounts of flour, water, starter and salt.

Accurate Baker's Math Adjustable Hydration Multiple Loaves Beginner Friendly

Golden sourdough loaf and an open-crumb slice with wheat on linen

Build Your Sourdough

Just choose a few options and we’ll calculate the rest.

1. How many loaves?

2. Choose loaf size

Small500 g RecommendedRegular750 g Large1,000 g

Custom weight

Weight per loaf, before baking. Enter 100–10,000 g.

3. What kind of dough do you want?

Easy to Handle~68% • Beginner-friendly Classic Sourdough~72% • Balanced Higher Hydration~78% • Stickier dough

Advanced Settings (Optional)

Starter Amount (%)

Starter weight ÷ total flour weight, including flour in the starter.

Starter Hydration (%)

100% means equal weights of flour and water in your starter.

Target Hydration (%)

Total water ÷ total flour, including both in the starter. Salt is fixed at 2% of total flour.

Recipe Result

For 1 loaf (750 g dough)

Total Hydration

72%

Total Dough Weight

750 g

Flour (extra to add): 388 g
Water (extra to add): 267 g
Active Starter: 86 g
Salt: 9 g

Bread Outcome Guide

Sourdough slice with a balanced open crumb, shown as a reference only

✔ Classic Dough

A Balanced Starting Point

A versatile dough style for many home bakers.

Illustration only — hydration alone cannot predict baking success, crumb structure or whether a loaf is too dry or too wet.

How to Use

From three simple choices to a ready-to-bake recipe.

Choose your loaf

Set how many loaves you want and pick a size for each one.

Choose your dough style

Start with the classic preset or pick an easier or higher-hydration dough.

Get your recipe

Click calculate for weights of flour, water, active starter and salt.

Frequently Asked Questions

What is a sourdough calculator?

It calculates how much flour, water, active starter and salt to use based on the number and size of your loaves and your chosen dough style.

What does hydration mean in sourdough?

Hydration is the weight of all water divided by the weight of all flour, expressed as a percentage. This includes the flour and water already in your starter.

Do I need to know baker's percentages?

No. Choose your loaf quantity, size and dough style, and the calculator handles the ratios. Advanced Settings are optional.

Can I make more than one loaf?

Yes. Choose between 1 and 10 loaves. The calculator scales all four ingredients to the total dough weight. The sizes shown are dough weights before baking.

Why is the bread image only a guide?

Flour, starter activity, fermentation, shaping and your oven all affect the final bread. The image is a reference and cannot guarantee a particular loaf or crumb.

What kind of starter should I use?

The default recipe uses active starter at 100% hydration, with equal weights of flour and water. Adjust Starter Hydration in Advanced Settings if your starter is firmer or wetter.