Sourdough Feeding Ratio Calculator
Treat retained starter as one ratio part, then enter flour and water parts relative to it. A 1:2:2 feed therefore adds twice the retained-starter weight in flour and water.
Flour to add 60 g
Water to add 60 g
Total after feeding 150 g
Boundary: The calculator returns feed weights only. It does not predict fermentation time, acidity, activity or readiness.
Formula
flour = retained starter × flour ratio; water = retained starter × water ratio; total = starter + flour + water
The calculator returns feed weights only. It does not predict fermentation time, acidity, activity or readiness.
How to use this calculator
- Keep the retained starter as the first and fixed ratio part.
- Enter flour and water parts independently; they do not need to match.
- The displayed total is the immediate post-feed weight before fermentation loss.
Worked example
With 30 g retained starter at 1:2:2, add 60 g flour and 60 g water for 150 g total starter.
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