Starter feeding calculator
Feeding ratios are written as starter : flour : water — 1:5:5 means one part mature starter to five parts each of flour and water. Tell the calculator how much starter you need and which ratio you are using, and it splits the weights for you.
How it works
Reading the ratio
The parts are by weight, not volume. A 1:1:1 feed doubles quickly and peaks within a few hours in a warm kitchen. A 1:5:5 feed takes far longer to peak, which is what you want when you need the starter ready in the morning rather than at midnight.
Matching the ratio to your schedule
Warm room and a tight schedule: feed more generously so the starter takes longer to peak. Cold kitchen or a starter straight from the fridge: a smaller ratio gets it active sooner. Temperature moves the timing more than the ratio does.
Making only what you need
Most home bakers keep far more starter than any recipe uses and discard the rest every day. Work backwards from the levain your loaf actually calls for, add a small reserve to carry forward, and the discard problem mostly disappears.
Frequently asked questions
How do I know the starter is ready to use?
It should have risen predictably — often doubled or more depending on the ratio — be domed rather than collapsed, and smell tangy and fruity rather than sharply acidic. Track when it peaks and feed on that rhythm.
Should I feed at 100% hydration?
Equal flour and water is the usual default and makes the arithmetic simple. Stiffer starters ferment more slowly and taste milder; the ratio field here works the same whichever hydration you keep.
What if my starter never doubles?
Most often it is too cold, or being fed too much too often for its current strength. Move it somewhere warmer, feed at a smaller ratio for a few days, and give it time — a young starter can take two weeks to become reliable.
Learn this properly
A calculator gets the numbers right. Getting the result right is a craft — our chefs teach it step by step, with feedback on your own bakes.
View the course