Sourdough Starter Calculator

Calculate flour, water, and starter amounts for feeding your sourdough starter. Adjust hydration, inoculation rate, and feeding schedule.

Inputs

Target Total (g)

Hydration (%)

Inoculation (%)

Feeding Schedule

Tab to move between fields

Results

Flour

80 g

Water80 g

Existing Starter40 g

Est. Peak Time6 hrs

Actual Hydration100%

How to Use This Calculator

Enter the target total weight of finished starter in grams.
Set the desired hydration percentage (100% = equal flour and water by weight).
Enter the inoculation percentage (existing mature starter as % of new batch).
Select your feeding schedule (once or twice daily).
The calculator shows flour, water, and existing starter amounts, estimated peak time, and actual hydration.

How the result changes with Target Total (g)

Target Total (g)	Flour
518	207 g
1,763	705 g
3,257	1,303 g
4,502	1,801 g

What each input means

Target Total (g): Total grams of starter you want after feeding. Include extra for what you need plus discard.
Hydration (%): Water as a percentage of flour. 100% = equal parts flour and water. Lower = stiffer starter.
Inoculation (%): Percentage of old starter relative to total. Lower = slower rise, more flavor development.
Feeding Schedule: How often you feed. Twice daily for warmer environments or before baking.

How this is calculated

Worked example, using the default values

Identify Input Parameters
4 parameters
Target Total (g) = 200, Hydration (%) = 100, Inoculation (%) = 20, Feeding Schedule = 1 = 4 input(s) provided
Calculate Flour
Flour
80 = 80
Calculate Water
Water
80 = 80
Calculate Existing Starter
Existing Starter
40 = 40

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