A sourdough starter feeding calculator takes your current starter weight, feeding ratio, and target hydration to give exact gram amounts for flour and water. Consistent feeding keeps your starter healthy and predictable.
80% = stiff starter • 100% = standard • 125% = liquid levain
Feeding Amounts
How to Feed Your Sourdough Starter
Feeding a sourdough starter means discarding most of it, then adding fresh flour and water. The discard removes accumulated acid (which would make bread too sour) and the fresh flour provides food for the wild yeast.
Weigh, Don't Measure by Volume
Always weigh starter, flour, and water in grams. Volume measurements are unreliable for starter maintenance — hydration directly affects fermentation speed and flavor.
Temperature Controls Everything
At 70°F (21°C), a 1:2:2 starter peaks in about 8-10 hours. At 80°F (27°C), it peaks in 4-6 hours. At 65°F (18°C), it takes 12-16 hours. Use feeding ratio to control timing at a given temperature.
Signs of a Healthy Starter
Doubles in size within expected time, develops a domed top before falling, has visible bubbles throughout, smells pleasantly sour and yeasty, and passes the float test when ripe.
FAQ
What is a 1:1:1 feeding ratio?
1 part starter : 1 part flour : 1 part water by weight. If you have 50g starter, use 50g flour and 50g water. This doubles the starter volume. Use this ratio for daily maintenance feedings.
What is a 1:5:5 feeding ratio?
1 part starter : 5 parts flour : 5 parts water. This significantly dilutes the starter, slowing fermentation. Use this when you want the starter to peak in 8-12 hours (for overnight timing) or when your starter is very sour.
What hydration should my sourdough starter be?
100% hydration (equal weight flour and water) is standard and easiest to maintain. 80% hydration (less water) creates a stiffer starter. 125% hydration creates a more liquid levain. Different hydrations affect rise speed and bread texture.
When is my starter ready to use?
Your starter is ready when it's doubled in size, has a domed top (not fallen), smells pleasantly tangy (not overly vinegary), and passes the float test — a small spoonful floats in water.
Is this tool free?
Yes, completely free.