Roast Profile Estimator
Get a starting point for charge temperature, first crack timing, total roast time and development time ratio. Treat the output as a hypothesis to test, not a recipe to follow blindly.
- First crack window
- 9.4 - 10.3 min
- Development time ratio
- 22%
- Total roast time
- 12.0 min
- Development phase
- 2.6 min
- Suggested drop temp
- 209°C
- Batch scope
- Home
Charge temperature starts from a machine-specific baseline, then adjusts by roughly 0.9°C for every degree the room differs from 22°C.
Timings start from roast-level targets and shorten for fluid-bed and sample machines, then lengthen for larger charges.
Reference temperatures
| First crack begins | 196 – 205°C |
|---|---|
| First crack ends | 205 – 212°C |
| Second crack begins | 220 – 230°C |
| Typical drop, light | 205 – 210°C |
| Typical drop, medium | 210 – 218°C |
| Typical drop, dark | 218 – 230°C |
Bean temperature readings vary between machines and probe placements. Your own logged history is always the better reference.
No estimator can know your machine. Use these numbers as a starting point for the first batch, then adjust based on what your own probe and your own palate tell you. Change one variable per batch so you know which adjustment produced the improvement.
Related tools and reading
Bean Probe
Every temperature in this estimator is measured at the bean probe. Its placement decides what the numbers mean.
Roast Profile Software
Log the actual curve and compare it against these estimates to build a picture of your machine.
Understanding First Crack and Development Time
What DTR actually measures and how to use it without becoming its prisoner.