Fermentation timing

Sourdough Bagel — Timing by Kitchen Temperature

Baseline: 1h bulk + 12h proof at 76°F. Adjust for your kitchen below.

Temperature × time table

Kitchen tempMultiplierBulk (h)Proof (h)
62°F2.20×2.226.4
68°F1.58×1.618.9
72°F1.23×1.214.7
76°F1.00×1.012.0
80°F0.78×0.89.4
85°F0.56×0.66.7

Calculator pre-set to Sourdough Bagel

Multiplier at 76°F
1×
Adjusted bulk ferment
1 h
Adjusted final proof
12 h
How the math works

Multipliers are piecewise-linear interpolations between reference points measured by Myhrvold et al. in Modernist Bread vol 3. 76°F is the baseline (1.0×); every 10°F drop roughly doubles fermentation time, and every 10°F rise roughly halves it.

Sources: Myhrvold et al., Modernist Bread vol 3 (temperature multipliers); Peter Reinhart — The Bread Baker's Apprentice, Bagel formula.