Decarb Loss Estimator
Decarb is a race between two reactions: THCA becoming THC, and THC becoming CBN. Set your oven and time to see how much active THC you end up with, and where the plateau is.
The Total THC line on the label, not THC.
Oven reads in
Home ovens often run 10 to 15 degrees off. An oven thermometer pays for itself in one batch.
Most of the THCA has converted and very little has moved on to CBN. This is where you want to pull the tray.
A kinetic model tuned to common home benchmarks, not a lab assay. Flower, grind and oven all vary. Use it to find the plateau, then confirm with a small test batch.
Want the reference table instead? See the decarb time and temperature guide.
Frequently asked questions
How much THC do you lose during decarboxylation?
At a typical home setting of 240 F (115 C) for about 40 minutes, roughly nine tenths of the THCA converts to THC and only a few percent of that THC moves on to CBN. The losses climb fast with heat: at 350 F, a quarter or more of the THC can degrade within an hour.
What temperature and time is best for decarbing cannabis?
Most home guides land between 220 and 250 F (105 to 120 C) for 30 to 45 minutes. Lower and longer preserves terpenes and gives a wider margin for error; hotter and shorter is faster but the plateau is narrow. The estimator shows the sweet spot for whatever temperature your oven actually holds.
Can you over-decarb cannabis?
Yes. Once the THCA has converted there is nothing left to gain, and every extra minute turns THC into CBN, which is more sedative than intoxicating. Over-decarbed flower infuses weaker and sleepier and tastes toasted.
Does decarb happen anyway when I bake the edibles?
Partly, and unreliably. A brownie's interior rarely gets hot enough for long enough to finish the job, so skipping decarb usually means a weak batch. Decarb first, then infuse, then bake gently.
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Read next
The guides and quick reads behind the numbers.
Run your decarb as a timer
Step-by-step Cook Mode timers in the Canabee app take the guesswork out of the oven. Free to start.