Coffee Calculators
Bean Degassing Calculator
https://www.coffeesizing.com/calculators/bean-degassing/
Estimate only — not a cupping score, a water lab or a roast profile. Confirm on a test brew.
Bean Degassing Calculator
Degassing is CO₂ leaving the bean after roast. Too soon and espresso pucks bloom, spray and channel; too late and aromatics fade. Roast level shifts the window: light often peaks later, dark earlier. Enter how you roasted and how old the bag is; this is rest folklore with numbers, not chromatography.
Inputs
Results
- Peak window start
- 0days
- Peak window end
- 0days
- In the window
- Yes
- Days until peak starts
- 0days
Recommended gear
Airtight coffee canister
Degassing needs a place to go. A valve bag or a vented canister beats a sealed mason jar that balloons.
Typical range: $20–$50
1Zpresso K-Ultra
Grind at shot time. Pre-ground coffee degasses in minutes, not days — this window is for whole beans.
Typical range: $80–$250
Espresso machine
Espresso is the canary: gushy pucks mean wait. Filter is more forgiving of day-two coffee.
Typical range: $400–$2,500
Calculation method
Each roast level maps to a peak start and end in days after roast: light 7–14, medium 5–10, dark 3–7. In-window is whether your rest day sits between those bounds. Days to peak is how long until the start, or zero if you are already there or past it. Filter can drink earlier; espresso usually wants the later side of the same band.
Exact formula
Light ≈ peak 7–14 d, medium 5–10 d, dark 3–7 d from roast. inWindow if daysSinceRoast is inside that band. daysToPeak = peakStart − days (floored at 0). Limits: Storage, origin, grind delay and bag valves omitted; windows are typical, not your lot.
Bloom is a clue
A towering bloom on a pour-over means gas is still leaving. That is related to degassing, not a reason to skip wetting. For espresso, that gas is a puck problem.
Frequently asked questions
Roasted today for a V60?
You can. Expect a vigorous bloom. Espresso on day zero is usually chaos. This window is biased toward espresso rest.
Frozen beans?
Freeze after the peak if you can, not instead of resting. Thaw sealed to avoid condensation, then grind.
The bag says ‘rested’.
Trust the roast date. ‘Rested’ on a supermarket bag can mean six weeks in a warehouse.
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