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Baking formulas and oven work

Sourdough Feeding Calculator

Turn a starter-to-flour-to-water feeding ratio into exact feed weights and the resulting build size.

Read the ratio in the stated order

g

Enter the ripe starter kept for this feed.

Use the first number in a ratio such as 1:4:4.

Enter flour parts relative to the starter part.

Enter water parts relative to the starter part.

Scaling a feed without changing it

Feeding notation describes relative weights in the order starter, flour, water. A 1:4:4 feed applied to 25 grams of starter adds 100 grams of flour and 100 grams of water.

The ratio does not state flour type, water temperature, ripening temperature, or readiness time. Those conditions belong in the feeding record.

Large feeds dilute accumulated acid and microorganisms more than small feeds. That can change ripening time even when final hydration is unchanged.

Prepare the next refresh

  1. Confirm the ratio order used by the source.
  2. Choose the retained starter weight.
  3. Weigh flour and water independently.
  4. Mark the container at the post-feed level.

The feeding result can lead to work that will check the resulting hydration and build only what a dough requires.

Turning ratio parts into feed weights

flour added = retained starter × flour parts ÷ starter parts; water added uses the same ratio

Method basis: Starter, flour, and water ratio parts are treated as relative weights scaled from the retained starter.

A one-to-four-to-four build

Suppose the kitchen records starter retained of 25 g, starter ratio part of 1, flour ratio parts of 4, water ratio parts of 4; flour to add of 100.0 g and water to add of 100.0 g follows. Use a container with enough headroom for the expected rise; build weight does not describe expansion volume.

Ratio accuracy at small scale

Ratio notation is compact but easy to reverse.

Container residue can matter in very small maintenance feeds.

Rounding should follow scale resolution rather than convenient whole numbers.

Feeding observations to retain

Write the ratio, retained starter, actual additions, flour blend, feed temperature, and observed peak interval on the same line.

If a target total matters, solve backward with a levain build rather than repeatedly changing the retained starter until the arithmetic happens to fit. That keeps the maintenance culture and production requirement distinct.

For a small scale that reads only whole grams, choose a build large enough that each part can be reproduced. A nominally exact ratio is not useful when several ingredients fall below the instrument’s resolution.

Clean transfer losses do not change the intended ratio, but they change available ripe starter. Weigh the usable build before allocating levain to dough and seed to the next feed.

Feeding-ratio questions

Will a 1:1:1 feed produce 100% hydration?

It does when the retained starter is already 100% hydration and flour and water are added in equal weights.

Can I enter a ratio such as 1:2:1.6?

Yes. Decimal parts work when a stiffer or more liquid feed is intentional.

Will the calculator predict peak time?

No. Inoculation, temperature, flour, acidity, and culture condition all affect timing.

Should discard be included?

Enter only the ripe starter actually retained for the new feed.