Sourdough Starter Feeding Calculator

Enter starter weight, starter:flour:water ratio, and starter hydration to calculate feed amounts, final starter mass, and resulting hydration.

Starter / seed (g)

Starter ratio

Flour ratio

Water ratio

Existing starter hydration (%)

Quick ratio

—Starter : flour : water by weight

—Flour to add

—Water to add

—Final starter

—Final hydration

Feeding ratios describe starter:flour:water by weight. Peak timing depends on starter health, temperature, flour, and ratio; this calculator does not predict an exact fermentation time.

Starter feed scale & reverse target

Use a starter:flour:water ratio to calculate the finished feed or reverse-solve the seed amount needed for a specific final starter mass.

Seed starter ratioFlour ratioWater ratioSeed starter (g)Target final starter (g)

—Seed starter

—Flour to add

—Water to add

—Final starter mass

Ready.

The ratio controls feed mass, not fermentation speed; temperature, inoculation, flour and starter condition affect timing.

Prefer weight when repeatability matters

Mass↔volume estimates depend on ingredient density and measuring technique. Pan substitutions can also change bake time and browning even when volume ratios match, while fermentation timing depends on temperature and dough conditions rather than one percentage alone.

Kitchen result basis is visible at the point of use

Direct mass↔mass and volume↔volume conversions are treated as exact unit conversions; mass↔volume results are labeled as ingredient-density estimates, while oven fan/gas and fermentation-related outputs keep their approximation boundaries visible.

Designed for fast kitchen use

The v263 interface keeps primary inputs and result trust in the first workflow, uses larger mobile controls, kitchen-friendly fractions where useful, and exposes the governing assumption instead of burying it below the calculator.