Sourdough Calculator

Calculate sourdough starter feeding ratios and levain builds.

Scratchpad (not saved)

g

Amount of existing starter

Parts flour per part starter

Parts water per part starter

g

Target levain weight (0 = use ratio)

What This Calculator Does

Calculate sourdough starter feeding ratios and levain builds.

It combines Starter Amount, Flour Ratio, Water Ratio, Target Levain Weight to estimate Total Levain Weight, Starter Amount, Flour Needed.

Formula & Method

Levain build follows ratio Starter:Flour:Water=1:r_f:r_w. If target total T is given, starter is S=\frac{T}{1+r_f+r_w}, then F=S\cdot r_f,\;W=S\cdot r_w.

Notation used in the formulas: R = Total Levain Weight; x_{1} = Starter Amount; x_{2} = Flour Ratio; x_{3} = Water Ratio; x_{4} = Target Levain Weight.

Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.

Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.

Inputs Used

  • Starter Amount: Amount of existing starter
  • Flour Ratio: Parts flour per part starter
  • Water Ratio: Parts water per part starter
  • Target Levain Weight: Target levain weight (0 = use ratio)

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