How To

Estimate THC Potency for Cannabis Edibles

When making edibles, it's important to estimate the potency of THC that will be present in each dose. Estimating THC potency starts with understanding the potency of the starting cannabis (weed) and calculating how much will carry over during the decarboxylation and infusion processes.

How to Estimate Potency

To estimate potency by hand, you start by calculating how much THC (in grams) is contained in the total mass of cannabis flower, trim or shake. You can do this by first identifying the THC potency (in percent) and multiplying it by the mass (in grams) that you are using:

grams of weed × THC potency (in %) = grams of THCA

Next, we take that product and multiply it by 90% to account for the amount of THCA that will actually get converted into active THC during the weed decarb process:

grams of THCA × 0.9 = grams of active THC to be infused

Then, we assume a certain amount of the active THC will be infused into the end product (e.g. butter, oil). We multiply the total grams of active THC that will be decarbed and multiply it by the percent to be infused based on the table below:

Product Infusion %
Butter 60%
Coconut Oil 60%
Pure Grain Alcohol 90%

grams of active THC × infusion percentage = grams of infused THC

This will provide you with the amount of active THC that will be infused into what amount of butter or oil you choose to infuse. To determine the amount of THC per service (dosage), you will need to divide the total active, infused THC by the total Tbsp. of butter or oil that you choose to infuse. Note: You may choose to infuse more butter than you will use in a given recipe. Keep this in mind.

grams of infused THC ÷ Tbsp. butter to infuse = THC per Tbsp. butter

Now, take the THC per Tbsp. of butter (or oil), and multiply it by the number of Tbsp. of butter (or oil) used in the recipe you will make. Divide this total THC per batch by the number of services yielded by the recipe to determine the dosage.

THC per Tbsp. butter × Tbsp. butter in recipe = THC per batch (whole recipe)

THC per batch ÷ number of servings = THC per service (dosage)

Potency Calculator

Note: At the moment, this calculator pertains to cannabutter and coconut oil infusions. Alcohol-based tinctures will typically result in a 50% greater potency.

There is 7 grams in 1/4 oz. of cannabis.
There are 16 Tbsp. in 2 sticks of butter (the amount used in our cannabutter recipe).
There are 16 Tbsp. in 2 sticks of butter (the amount used in our cookie recipes).
There are 12 cookies in a typical batch of cookies.