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
Bulk fermentation is the single most important stage in sourdough baking. Get it right and your dough will be easy to shape, spring well in the oven, and produce an open crumb. Get it wrong — in either direction — and no amount of skill at shaping or scoring will rescue the loaf.
What is bulk fermentation?
Bulk fermentation — also called the first rise or first proof — is the period between mixing your dough and dividing or shaping it. During this time the dough ferments as one mass, hence “bulk.” Two things happen at once, and your goal is to develop enough of both without going too far, which breaks down the gluten and leaves the dough slack and unworkable.
When does bulk start? Count bulk from the moment the starter goes into the dough. An autolyse of flour and water beforehand is not part of bulk, because there is nothing to ferment it yet. Salt and stretch-and-folds happen during bulk, not before it, so do not wait for the last fold to start the clock. Some recipes time bulk from the salt addition instead; read which point yours means, then mark the dough’s level in the container so the rise you judge later is measured from the same point.
How long does bulk fermentation take?
There is no single correct answer — bulk time depends on dough temperature, starter percentage, and flour type. The figures below come from our bulk calculator’s model: white flour, 20% starter, 75% hydration and a 50% rise. In the same model, wholemeal ferments about 15% faster and rye about 30% faster.
The chart below extends those three points across the full range (same baseline). Moving from a cool kitchen to a warm one can cut the same dough’s bulk time to roughly a third, which is why dough temperature matters more than any timer.
| Dough temperature | Approximate bulk time |
|---|---|
| 16°C / 61°F | 8.5–11.5 hours |
| 18°C / 64°F | 7–9.5 hours |
| 21°C / 70°F | 5.5–7.5 hours |
| 24°C / 75°F | 4.5–6 hours |
| 25–26°C / 78°F | 3.5–5 hours |
| 28°C / 82°F | 3–4 hours |
At 10% starter, expect those windows to run about 40% longer (our calculator’s model). For a time estimate tuned to your exact conditions, use the bulk fermentation calculator.
Why temperature is the biggest variable
Warmer dough ferments faster. My planning model assumes the time roughly halves for every 8°C (14°F) warmer, so a dough that takes 10 hours at 20°C is estimated at about 5 hours at 28°C. That is a working assumption, not a measured rule, but it is why bakers watch dough temperature so closely.
Measure dough temperature, not room temperature. Friction from mixing warms the dough 2–4°C above ambient. Insert a probe thermometer into the centre of the dough; this one habit makes your timing far more predictable. Aim for a target dough temperature of 24–26°C (75–79°F), which gives a manageable 3.5 to 6 hour window with 20% starter in white flour.
How starter percentage affects bulk time
Starter percentage is the weight of starter as a proportion of total flour — most recipes use 10–25%. More starter means more yeast and bacteria from the start, so fermentation is faster. Halving your starter percentage adds about 40% to bulk time at the same temperature, and doubling it takes about a third off. In our calculator at 24°C, 10% starter gives about 6 to 8 hours and 20% about 4.5 to 6.
Reading dough signs: when bulk is done
The time estimate is only a starting point — the dough itself tells you when it is ready. Look for all four of these together rather than trusting any one alone, and confirm the final proof later with the sourdough poke test. Once bulk is done you divide, bench-rest, and shape; for the whole shaping-to-bake stage that follows, see how to proof sourdough.
Related calculator
Bulk Fermentation Time Calculator
Enter dough temperature, starter %, flour blend, hydration and target rise to estimate bulk fermentation time — with fold times and a full bake schedule on the clock.
Troubleshooting under-fermentation
Under-fermented dough is tight and stiff at shaping, does not spring back when poked, and tears when handled. The loaf has poor oven spring, a dense crumb, and a thick crust — see why is my sourdough dense for the full crumb-by-crumb diagnosis.
Watch for
- Dough temperature too low — measure it with a probe, not the room.
- Starter not active enough at mixing — used too early or too late after feeding.
- Starter percentage too low for the conditions.
Fix for next time: measure actual dough temperature; if below 22°C, find a warmer spot or use warmer water, and confirm your starter is at peak when you mix. Mid-bake: if caught early, give the dough more time somewhere warmer; if already shaped and tight, extend the final proof at room temperature before baking.
Free Sourdough Baking Playbook (printable PDF)
A printable PDF companion for the sourdough calculators and guides.
Troubleshooting over-fermentation
Over-fermented dough is extremely slack and sticky, spreads instead of holding shape, and tears when you try to build tension. The baked loaf is flat, dense, and can be gummy.
Watch for
- Bulk simply ran too long.
- Dough temperature spiked during fermentation — common in summer.
- Starter percentage too high for the conditions.
Fix for next time: reduce bulk time, lower dough temperature with cooler water, or drop the starter percentage. Mid-bake: do not try to fold and recover it. Shape immediately and gently, skip the extended final proof, and bake straight away — or cold-retard for 30–60 minutes to firm it up before scoring. It will not be your best loaf, but it may still be good to eat.
Stretch and fold during bulk
Most recipes include stretch and fold sets during bulk — typically every 30 minutes for the first 2–3 hours. Unlike punching down yeasted bread, this is not about degassing; it builds gluten strength. The dough becomes noticeably stronger with each set, and by the third or fourth it should hold its shape clearly when lifted.
- 1Wet your hand Damp hands stop the dough sticking so you can work it without tearing.
- 2Stretch one side up Grab one side, lift it as far as it will go without tearing, and fold it over the top.
- 3Rotate and repeat Turn the bowl 90° and repeat — four folds total completes one set.
- 4Rest between sets Wait about 30 minutes, then repeat. After the final set, leave the dough undisturbed for the rest of bulk.
A typical schedule front-loads the folds into the first two hours, then leaves the dough alone to finish rising:
| Time into bulk | What to do |
|---|---|
| 0:00 | Mixing complete, bulk begins |
| 0:30 | Stretch and fold, set 1 |
| 1:00 | Stretch and fold, set 2 |
| 1:30 | Stretch and fold, set 3 |
| 2:00 | Stretch and fold, set 4 (final set) |
| 2:00 to end | Leave undisturbed until the doneness signs appear |
Stiffer or lower-hydration doughs need fewer sets; slack, high-hydration doughs can take an extra early set. Stop folding once the dough holds its shape and feels airy, even if that comes before the fourth set.
Cold bulk fermentation
Many recipes use a room-temperature bulk followed by a cold final proof, but you can also extend bulk itself into the fridge. Cold bulk at 4°C slows fermentation dramatically without stopping it, which gives you enormous scheduling flexibility. Our bulk model does not cover fridge temperatures, so go by the dough rather than a multiplier.
If you go this route, end the room-temperature part early, while the dough has only started to rise, then shape, then refrigerate for 8–24 hours. Final-proof at room temperature for 1–2 hours before baking.
If the dough went into the fridge before bulk finished, it has kept fermenting there, only slowly. To finish it:
- 1Check the rise you already have Compare the dough with the level you marked at mixing. The rise it made before and during the fridge counts toward the 50–75% target.
- 2Let it warm on the counter Cold dough barely moves at first. Leave it covered at room temperature and let it come back up before you judge it.
- 3Finish on the dough signs Carry on until it shows the four signs above: the rise, a domed and bubbly surface, the jiggle and an airy stretch. Do not restart the clock from zero.
- 4Or shape it if it is nearly there If the dough already shows most of the signs when it comes out, shape it and give it a cold final proof instead of warming it.
Choose a stopping point and develop strength early
Set a target before you mix, then observe how your flour behaves at that target. For wheat dough, the bulk calculator now offers optional protein-based aliquot suggestions and manual control. Those reference points are not a rule for rye paste or a guarantee that a particular clock time is correct.
An aliquot is most useful when sampled consistently and kept beside the dough. If the sample and main dough are at different temperatures, their rise can diverge. Record when the sample was removed: starting after initial strength development differs from sampling immediately at mix.
Use folds early to organise the dough, then leave a strengthening, aerated mass to rise without unnecessary disturbance. For method selection see coil folds versus stretch and folds. If mixing is the difficulty, choose a resting workflow that you can repeat reliably.
