Sourdough Starter Manager
Log each feed, watch your starter rise in a 3D jar and record when it peaks. After two feeds it learns your own starter’s timing, so you know when it will be ready.
- See the rise against the clock
- Learns your starter’s peak time
- Free, no account needed
Feeding a sourdough starter means adding fresh flour and water to the existing culture so the wild yeast and bacteria have food to consume. Done consistently, feeding keeps your starter strong, active, and ready to leaven bread. Done poorly — wrong ratios, wrong timing, wrong temperature — it leaves you with a sluggish or unbalanced culture.
What happens when you feed
When you add flour and water, the wild yeast and lactic acid bacteria begin consuming the sugars in the flour. Yeast produces carbon dioxide (which makes bread rise) and ethanol. Bacteria produce lactic and acetic acids, which give sourdough its flavour and help preserve the finished loaf.
After each feed the culture moves through four phases. Your job is to use the starter at or just before peak, then feed it again before it collapses too far and the acid load builds up. To learn when your own starter peaks, log each feed in the sourdough starter manager.
- 1Lag phase The first 1–2 hours after feeding. Minimal visible activity while the culture wakes up and starts metabolising the fresh flour.
- 2Rise phase The culture accelerates, producing CO₂ and expanding in volume. Bubbles appear throughout and the surface begins to dome.
- 3Peak The highest point it reaches, often around double, domed and airy. Doubling can come hours earlier. This is the moment to use the starter for baking.
- 4Fall The food is depleted, the starter deflates, and acids accumulate. Feed again around here — not after it has fully collapsed.
Feeding ratios explained
A feeding ratio describes the proportion of old starter to flour to water, always by weight, in the format starter : flour : water. The higher the ratio (more food per unit of starter), the longer it takes to peak and the milder the flavour. A lower ratio peaks faster but produces a more acidic culture.
You are not limited to round numbers. A 1:3:4 feed is wetter, not stiffer: with a 100%-hydration seed its final hydration is about 129%. A 1:2:3 feed gives about 140%. The retained seed contributes both flour and water, so feed-water ÷ feed-flour alone is not the final hydration. The sourdough feeding calculator gives exact grams for any ratio and hydration.
How much starter to keep
Most home bakers keep far more starter than they need. You only need a small seed to feed from — typically 10–30g. Everything else is discard.
A practical approach: decide how much starter your recipe needs (usually 100–200g), then back-calculate from your chosen ratio. For a 1:5:5 feed producing 200g total, keep 18g starter and add 91g flour and 91g water. Keeping the maintained amount small wastes less flour and keeps the acid load low — carrying over too much old starter starves the culture faster.
Discard: what it is and what to do with it
Every time you feed, you remove most of the old starter before adding fresh flour and water. That removed portion is discard. It is not waste — it is unfed starter with a mildly sour flavour that works well in many recipes: pancakes and waffles, crackers, pizza dough, banana bread and muffins, and flatbreads.
Discard keeps in a separate container in the fridge for up to a week.
Counter vs fridge: which schedule fits you
There is no single right schedule — it depends on how often you bake. Match the routine to your habits rather than forcing daily feeds you will not keep up with.
A starter that goes too long between feeds, on the counter or in the fridge, often grows a layer of grey liquid on top. That is hooch, a sign of hunger rather than spoilage; sourdough starter hooch explains whether to pour it off or stir it in.
Related calculator
Sourdough Starter Feeding Calculator
Exact starter, flour, water, and discard for 1:1:1, 1:5:5, or any custom feeding ratio, with a ratio chart and peak times.
Which flour to feed with
Different flours feed the culture at different speeds. You can lean on the faster ones to wake a sluggish starter, or stick with a steady base for predictability.
Free Sourdough Baking Playbook (printable PDF)
A printable PDF companion for the sourdough calculators and guides.
Water for feeding
Use room-temperature water. If your tap water is heavily chlorinated, leave it in an open container for 30 minutes before using, or use filtered water — chlorine can inhibit bacterial activity.
Water temperature matters most in cold kitchens. Slightly warm water (26–28°C) helps get the culture active faster in winter, while cold water slows it from the moment of feeding.
Signs your feeding routine is working
When your ratio, flour, and timing are locked in, the starter behaves predictably. Look for all of these together.
If your starter is inconsistent — sometimes doubling in 4 hours, sometimes 12 — the usual culprits are temperature swings, inconsistent flour, or varying how much old starter you carry over. Lock in all three and results steady out.
Common feeding mistakes
Watch for
- Feeding too much at once — 1:10:10 overwhelms a sluggish starter; build up from 1:1:1.
- Feeding at the wrong time — wait until it is past peak and starting to fall, not fully collapsed and starving.
- Using cold water in winter — it slows the culture immediately; use room-temperature water year-round.
- Not discarding enough — too much carried-over starter lets the old acid load dominate the fresh feed.
- Switching flour brands mid-routine — different protein and yeast levels can throw off timing for days.
Stiff, standard and liquid starter builds
Choose the feed amount separately from the final consistency. With 10g seed at 100% hydration, the seed already contains 5g flour and 5g water. To add 50g flour and finish at 50% hydration, add 22.5g water: the final build contains 55g flour and 27.5g water. A simple 1:5:2.5 feed would finish closer to 54.5%, not exactly 50%.
| Desired final hydration | Seed at 100% | Flour to add | Water to add | Build weight |
|---|---|---|---|---|
| 50%, stiff | 10g | 50g | 22.5g | 82.5g |
| 100%, standard | 10g | 50g | 50g | 110g |
| 125%, liquid | 10g | 50g | 63.75g | 123.75g |
These examples describe mass balance, not guaranteed flavour or rise times. A stiff culture does not rise or peak exactly like a liquid one; use a marked container and establish a fresh baseline after changing its consistency. The feeding calculator now includes retained-starter hydration and final-hydration build presets.
For less waste, keep a small maintenance jar and build the recipe levain separately. Scale the build before feeding rather than repeatedly discarding large quantities. For breaks between bakes, use the storage guide.
