Calculator
How long do I decarb for?
Pick your oven temperature and get the time window, how much of the THCA actually converts, and what the heat costs you in aroma.
Decarb chart
Every workable temperature, what it costs you, and how long it takes. Lower and slower keeps more aroma; hotter and faster is easier to overshoot.
| Temperature | Time | Converted | Aroma |
|---|---|---|---|
| 200 °F / 93 °C | 60-90 min | 70-85% | Most aroma survives |
| 220 °F / 104 °C | 45-60 min | 80-92% | Good aroma retention |
| 240 °F / 115 °C | 30-45 min | 85-95% | Noticeable aroma loss |
| 250 °F / 121 °C | 25-30 min | 85-95% | Noticeable aroma loss |
| 265 °F / 129 °C | 18-25 min | 85-95% | Most monoterpenes gone |
| 280 °F / 138 °C | 12-18 min | 80-92% | Aroma largely destroyed |
Questions people ask
- What temperature should I decarb at?
- 240 °F / 115 °C for 30 to 45 minutes is the standard, and it is the standard because it sits at the balance point: hot enough to convert almost all of the THCA, cool enough that a useful share of the monoterpenes survive. Going lower keeps more aroma at the cost of completeness; going higher is faster but the window for overshooting narrows sharply.
- Why does my flower lose weight in the oven?
- Two things are leaving. Most of it is water, and the rest is carbon dioxide — decarboxylation is literally the loss of a carboxyl group, which is where the name comes from. That CO₂ is also why 1 g of THCA can only ever become 0.877 g of THC. The missing mass is not a mistake, it is the reaction working.
- Can I skip decarbing if I am going to cook it anyway?
- Partly, and unreliably. Some conversion happens during a long, warm infusion, which is why raw flower in a slow cooker is not a total loss. But infusion temperatures are lower and the material is suspended in fat, so conversion is patchy and you cannot predict it. Decarbing first is the difference between a known starting point and a guess.
- Is longer safer?
- No, and this is the most common expensive mistake. Conversion peaks and then reverses: THC begins turning into CBN the moment the peak passes, and that change is permanent. An extra twenty minutes does not buy insurance, it burns potency. Use a timer and take it out.
- Does decarbing smell?
- Yes, strongly, and an oven is the worst offender because it vents. A sealed mason jar in a water bath or a sous vide bag contains almost all of it, which is the main reason people use those methods rather than any advantage in conversion.
Decarbed and ready? The infusion calculator picks up from here.
Every constant behind these numbers is written down, with its source, on the how this is calculated page. If you think one of them is wrong, say so — that page exists to be argued with.