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Levain Builder
Calculate levain builds and estimate fermentation time
A levain (or leaven) is an off-shoot of your starter built specifically for a recipe. Building a levain lets you control timing and quantity without disrupting your main starter.
Feed Ratios Explained
The ratio 1:5:5 means 1 part starter, 5 parts flour, 5 parts water. Higher ratios = more food = longer fermentation time.
Signs of Readiness
- Doubled or tripled in volume
- Domed top (not yet collapsed)
- Passes the float test
- Smells pleasantly tangy
Build Parameters
Configure your levain build
How much levain you need for your recipe
Levain Recipe
Ingredients for your build
Mature Starter18g
Flour91g
Water91g
Total Levain200g
Estimated Peak Time
10 hours
at 75°F with 1:5:5 ratio
Look for doubled volume and a domed top. The levain should float in water when ready.
Ratio Timing Guide
Approximate times at 75°F room temperature
| Ratio | Peak Time | Best For |
|---|---|---|
| 1:1:1 | 3-5 hours | Quick refresh, same-day bake |
| 1:2:2 | 5-7 hours | Morning mix for evening bake |
| 1:3:3 | 7-10 hours | Overnight levain (warm room) |
| 1:5:5 | 10-14 hours | Standard overnight levain |
| 1:10:10 | 14-18 hours | Long overnight, cool room |
Levain Tips
- Use your starter at peak: A young, active starter will give you a more vigorous levain.
- Flour choice matters: Whole grain flours ferment faster. Use some whole wheat or rye for a more active levain.
- Temperature control: Use a proofing box or oven with light on to maintain consistent temperature.
- Don't over-proof: A levain past peak (collapsed) will be weaker. Better to use it slightly early than late.
- Float test: Drop a small spoonful in water. If it floats, it's ready. If it sinks, give it more time.