Fermentation timing
Spelt Hearth Loaf — Timing by Kitchen Temperature
Baseline: 3h bulk + 6h proof at 76°F. Adjust for your kitchen below.
Temperature × time table
| Kitchen temp | Multiplier | Bulk (h) | Proof (h) |
|---|---|---|---|
| 62°F | 2.20× | 6.6 | 13.2 |
| 68°F | 1.58× | 4.7 | 9.5 |
| 72°F | 1.23× | 3.7 | 7.4 |
| 76°F | 1.00× | 3.0 | 6.0 |
| 80°F | 0.78× | 2.3 | 4.7 |
| 85°F | 0.56× | 1.7 | 3.4 |
Calculator pre-set to Spelt Hearth Loaf
- Multiplier at 76°F
- 1×
- Adjusted bulk ferment
- 3 h
- Adjusted final proof
- 6 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.