How to Calculate Edible Potency
Calculating potency is the most difficult part when making edibles because most people don’t know the cannabinoid content of their starting material, which requires access to a testing facility. The good news is you can use average THC percentages of the starting material to help ballpark the potency level of your edibles. What I want to emphasize is that edibles made from 7 grams of top-shelf, California sun-grown OG Kush flowers are going to be significantly stronger than edibles made from 7 grams of synthetically grown trim. Need help determining the potency of your cannabis? Besides a visual inspection, you can do a quick smoke test and rank it among the other strains you have smoked. The following table shows the range of average THC percentage by weight in each type of starting material:
*Please note that this data pertains to THC-rich strains (i.e. the stuff that is intended to get you high, most ‘street weed’) as opposed to medically oriented high-CBD strains, which typically contain lower levels of THC. With regards to the bud itself, legal states like Colorado will average more like 18% THC, whereas non-legal states could be closer to 10% THC.
The easiest way to calculate the amount of cannabis starting material required is to back into the number based on what you consider to be a personal dose of THC. For some people, this is 5mg of THC, and for others it’s in excess of 100mg. For more on how to choose the right dose for you, check out our comprehensive consumption guide.
The next step is to determine how many servings the recipe makes; i.e. does it make 12 or 24 cookies. Multiply the number of servings in the recipe by the desired THC content in each serving; this will yield the total amount of THC in mg required to achieve your desired potency level. Although this may sound confusing, my friend Jeff the 420 Chef has put together an easy-to-use calculator to help you determine how much cannabis material and oil/butter should be used for any recipe. It will also break down the mg of THC/CBD in each serving size.
If using already infused coconut oil and it's too strong, you can dilute it with additional coconut oil. On the other hand, if it's too weak, you can re-infuse or add a small amount of highly concentrated cannabis coconut oil to the weaker batch. It may take a few batches before you achieve your perfect dose, but it will get easier and more precise each time.