Sourdough Starter Feeding Ratio (1:1:1, 1:2:2, 1:5:5)

1 part

Mature starter (inoculant) — Taken at or just past peak activity — when it has roughly doubled and the dome has not yet collapsed; discard the rest or use in pancakes, crackers, etc.

1–5 parts

Fresh flour — White bread flour for neutral maintenance; whole wheat or rye to boost activity; the flour number sets the food supply

1–5 parts (matching flour)

Fresh water — Room-temperature or lukewarm; matching the flour weight keeps the starter at 100% hydration (equal flour and water by weight)

1. Weigh the desired amount of mature starter into a clean jar. 2. Add flour and water in the chosen ratio; stir vigorously until no dry flour remains. 3. Mark the jar at the starting level (rubber band, tape) to track rise. 4. Keep at 24–27 °C (75–80 °F) for predictable timing. 5. The starter is ready to use when it has peaked (roughly doubled, surface domed and bubbly, passes the float test). 6. Use within 1–2 hours of peak, or refrigerate to hold.

• Temperature is the hidden variable: the same 1:2:2 ratio peaks in 6 hours at 26 °C and 14 hours at 20 °C — calibrate by temperature, not just by ratio.
• A consistently refrigerated starter needs to be revived with two or three 1:1:1 feedings at room temperature before it is reliably active enough for bread.
• The float test (dropping a teaspoon of starter in water) works if the starter is actively fermented and gassy — a thin, dense starter sinks even at peak. Use it as one signal among several, not the sole indicator.
• Whole rye flour fed at even 5–10% of the flour weight in each feeding significantly boosts fermentation speed; its high enzyme content and wild yeast population invigorate a sluggish culture.
• Discard before each feeding is not waste management — it prevents the accumulation of metabolic byproducts that would eventually acidify the environment beyond what yeast tolerates.
• For predictable baking schedules, maintain the starter at 1:2:2 or 1:3:3 and use the refrigerator as a pause button: once it peaks, refrigerate it and use within 1–3 days.
• When building a levain (a large, single-use preferment) for a bake, you can use a ratio like 1:5:5 and time it so it peaks exactly when you need to mix the final dough.

• 1:1:1 (same-day, 4–6 h at 24 °C)

  Fast rise; high microbial density; relatively acidic result; use when you need the starter ready in a few hours or when maintaining a very active culture

• 1:2:2 (standard, 6–10 h at 24 °C)

  Most common maintenance ratio; starter doubles in a predictable window; moderate acidity; suits bakers who feed in the morning and bake in the evening

• 1:3:3 (overnight at room temp)

  Peaks in 8–12 hours at 21–24 °C; useful for feeding before bed and mixing first thing in the morning

• 1:5:5 (mild, 12–16 h at 24 °C)

  Highly diluted; slow rise; yeast activity dominates over bacteria early in the cycle, producing a milder, less sour levain; preferred for sweet doughs or mild-flavored loaves

• 1:10:10 (extreme, cold or long schedule)

  Takes 24+ hours at room temperature or can be held in the refrigerator for several days; the microbiome shifts toward more acetic acid production over the long cycle

• Stiff starter (1:2:1, 65% hydration)

  Less water than flour in the feed; produces a stiffer culture that favors acetic acid bacteria; used for Altamura-style breads and very sour San Francisco sourdough

• Liquid starter (1:2:3)

  More water than flour; very active and fast-rising; mild flavor; favored for quick baking schedules and beginner-friendly maintenance

• Baker's Percentage System

  Feeding ratios translate to baker's percentages within the levain sub-formula

• Sourdough Hydration (65–85%)

  The starter's hydration (typically 100%) is part of the dough's total hydration calculation

• Salt to Flour Ratio in Bread (1.8–2.2%)

  Salt is never added to the starter; it enters only in the final dough and affects fermentation timing indirectly

• Bread Hydration (Lean Dough)

  Starter activity and feeding ratio affect how quickly the final dough reaches the optimal fermentation state

1. 1.Tartine Bread — Chad Robertson (Chronicle Books, 2010)
2. 2.The Sourdough School — Vanessa Kimbell (Kyle Books, 2018)
3. 3.Flour Water Salt Yeast — Ken Forkish (Ten Speed Press, 2012)
4. 4.The Art of Fermentation — Sandor Ellix Katz (Chelsea Green, 2012)
5. 5.Modernist Bread — Nathan Myhrvold & Francisco Migoya (The Cooking Lab, 2017)

Confidence: high