1:3:3 Sourdough Starter Feeding Chart to Make 300g Levain (43g : 129g : 128g)
Balanced mid-ratio baker's math to build 300g of active levain (100% Liquid) for an 8 - 10 hrs ripening window.
Feed 1:3:3 and you get 43g seed starter, 129g flour and 128g water, adding up to the 300g you actually need. That 100% Liquid culture peaks in 8 - 10 hrs at 75°F. Add the 20g buffer and the numbers shift to 46g / 137g / 137g for a 320g jar. Perfect for 8–10 hour overnight counter build (cool room).
- Exact 300g Build
- 43g : 129g : 128gStarter : Flour : Water (1:3:3)
- 300g + 20g Jar Reserve
- 46g : 137g : 137gBuilds 320g total (0g discard waste)
- Estimated Peak Window
- 8 - 10 hrsAt 74°F–76°F (23.5°C–24.5°C)
- Levain Hydration
- 100%8–10 hour overnight counter build (cool room)
Zero-Discard 1:3:3 Starter Math at 300g (43g : 129g : 128g)
Every row recalculates the 1:3:3 ratio from scratch so the seed, flour and water columns stay internally consistent.
| Levain Yield to Build | Seed Culture (1 Part) | Added Flour (3 Parts) | Added Water (3 Parts) | Ripening Window at 75°F |
|---|---|---|---|---|
| 320g target ([Baseline]) | seed 46g | flour 137g | water 137g | ripe in 8 - 10 hrs |
| 300g target (Trimmed Read) | seed 43g | flour 129g | water 128g | ripe in 8 - 10 hrs |
| 280g target (Extended Read) | seed 40g | flour 120g | water 120g | ripe in 8 - 10 hrs |
| 310g target (Compact Read) | seed 44g | flour 133g | water 133g | ripe in 8 - 10 hrs |
| 290g target (Generous Read) | seed 41g | flour 124g | water 125g | ripe in 8 - 10 hrs |
Custom Batch Recalculation Engine
Fine-tune starter hydration between 50% stiff and 125% liquid while keeping your starter feeding ratio × target weight ratios locked.
Balancing Yeast Density & Acidity with a 1:3:3 Ratio (300g Levain Build)
Scaling to 300g means every gram is shared across 7 parts (42.9g each). The 43g seed portion carries the entire wild yeast and lactobacilli population, the 129g flour portion supplies the substrate, and the 128g water portion sets the mobile phase for both.
If your culture is sluggish or smells sharply of vinegar, the ratio is usually not the culprit — the culture is. Two consecutive warm 1:3:3 refreshes, each feeding 129g of fresh flour against 43g of tired seed, strip out accumulated acetic acid and restore yeast vigour faster than any other single intervention.
Zero-Discard Scraping Method for 300g Levain (1:3:3)
- Reserve the 20g Jar Remainder (46g): Tip your culture jar and scrape every last gram into a clean vessel — roughly 46g — so nothing is discarded.
- Combine the 1:3:3 Feed (137g + 137g): Stir 137g of flour into 46g of seed, then add 137g of room-temperature water until no dry flour remains.
- Mark the 320g Target: Level the jar and tape a line at the starting height; the culture should dome well past it within 8 - 10 hrs at 75°F.
- Harvest 300g and Return 20g: Pour 300g of peaked levain into your dough, then scrape the surviving 20g back into the jar and refrigerate at 38°F.
Technical Q&A: 1:3:3 Sourdough Starter Feeding Chart to Make 30
What is the real difference between 1:3:3 and a 1:1:1 feed?
A 1:1:1 feed keeps one third of the batch as seed and peaks fastest; 1:3:3 keeps one 7th, so it ripens more slowly but with far less inherited acidity.
Can I make 300g of levain with a stiff 50% starter?
A 1:3:3 refresh already produces 100% liquid levain. For a 50% final hydration you would instead use 129g flour and 129g water.
Why does my 1:3:3 levain smell sour instead of sweet?
Sourness means the seed was over-acidic going in. Feed 129g of fresh flour against 43g of the old starter twice in a row at 78°F and the taint disappears.