The Starter Clock

Sourdough Fermentation Predictor

121234567891011Peak: 9h 2mUSE WINDOW: 6h 48m – 11h 18m
60°F70°F75°F80°F90°F 72°F
STARTER
1:5:5 Feeding Ratio
Flour Type
Feeding Ratio
Kitchen Temperature
72°F
55°F 65°F 75°F 85°F 95°F

Prediction

Peak Activity 9h 2m after feeding
Use Window 6h 48m – 11h 18m optimal for baking
Flavor Profile

Balanced fermentation → mix of lactic and acetic. Balanced, slightly nutty, mild tang. Pleasant, complex tang.

Settings

Flour 80% white + 20% whole wheat — Forkish's standard. WW adds sugars and minerals for vigor.
Ratio Standard build — close to Forkish's maintenance (1:5:4 at 80% hydration). 6-9 hours at room temp.

Tips

  • Float test (Robertson): drop a spoonful in water. If it floats, the leaven has sufficient CO2 and is ready to mix into your dough. This indicates active yeast, not necessarily peak fermentation.