Sourdough Calculator for Bread Dough

This sourdough calculator gives the ingredient amounts for your bread dough by baker’s percentage: enter total flour, hydration, salt and starter and the amounts to add appear at once. With 1000 g of flour, 70% hydration and 20% starter you add 900 g of flour and 600 g of water.

Source: Wikipedia – Bäckerprozent (Baker's percentage). Updated: 2 October 2026.

Total flour

All the flour in the dough, including the flour in the starter – it equals 100%

Hydration (water)

Total water as a percentage of total flour, usually 65–80% for bread

Salt

Typically 1.8–2.2% of the flour

Fresh yeast (optional)

0 for pure sourdough bread; otherwise about 0.5–1%

Starter

Weight of ripe starter as a percentage of total flour, usually 10–30%

Starter hydration

100% = equal parts flour and water (wheat starter), 80% = a stiffer starter

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Result

Dough amount: Total dough 1,720 g – from 1,000 g of flour and 700 g of water
Ingredients for the final dough: Ingredient Amount Baker’s percent
Flour (fresh) 900 g 90 %
Water (fresh) 600 g 60 %
Starter (sourdough) 200 g 20 %
Salt 20 g 2 %
Total dough weight 1,720 g 172 %
Working: Total flour 1,000 g = 100%; total water 700 g = 70 % hydration.
The starter (200 g) consists of 100 g of flour and 100 g of water at 100 % hydration. Both are already deducted from total flour and water.

Ingredient	Amount	Baker’s percent
Flour (fresh)	900 g	90 %
Water (fresh)	600 g	60 %
Starter (sourdough)	200 g	20 %
Salt	20 g	2 %
Total dough weight	1,720 g	172 %

How it is calculated

Baker’s percentages express every ingredient relative to the total flour, which always equals 100%. 70% hydration means 70 g of water per 100 g of flour. That makes recipes comparable regardless of dough size and easy to scale up or down.

How the tool handles sourdough

A ripe sourdough starter contains flour and water itself. At 100% hydration it is half flour and half water. The calculator counts both toward total flour and water and subtracts them from the ingredients you add – otherwise the dough would end up too wet or too dry. Example: 1000 g total flour, 70% hydration, 2% salt and 20% starter (100% hydration):

Starter: 200 g, containing 100 g of flour and 100 g of water.
Add: 900 g of flour, 600 g of water (700 − 100) and 20 g of salt.
Total dough: 1720 g.

Tips on hydration and quantity

Higher hydration gives a more open crumb but a stickier dough. Whole-grain flour absorbs more water than white flour. To change the flour weight of an existing recipe, simply recalculate with the same percentages. For pizza dough there is the pizza dough calculator; general ratios are solved by the proportion calculator. The figures are guidelines – flour type, room temperature and the maturity of your starter change the result.

Frequently asked questions

What are baker’s percentages?

All ingredients are given as a percentage of the total flour, which equals 100%. 1000 g of flour, 700 g of water and 20 g of salt are 100%, 70% and 2%.

How do I calculate hydration for sourdough bread?

Total water divided by total flour times 100 – including the water and flour inside the starter. The calculator counts both automatically.

How much starter do I need?

Usually 10 to 30% of the total flour. More starter shortens the rise; a small share lengthens it and often adds flavor.

How much salt goes into bread?

About 2% of the flour weight is typical, which is 20 g per kilogram of flour.

Can I use the calculator for bread with yeast?

Yes: set the starter to 0 and enter the fresh yeast as a percentage of the flour, about 0.5 to 1%.

Sources and legal basis

As of: 2 October 2026 · Editorial policy