How is total THC calculated

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In Connecticut, total Tetrahydrocannabinol (THC) is calculated using the following formula:


Total THC = (THCA x 0.877) + THC 


THCA is multiplied by 0.877 because not all THCA changes to THC when it is heated. The definition of THC includes all isomers of Tetrahydrocannabinol including, but not limited, to Delta-7, Delta-8, Delta-9 and Delta-10 and any material, compound, mixture or preparation which contain their salts, isomers and salts of isomers, whenever the existence of such salts, isomers and salts of isomers is possible within the specific chemical designation, regardless of the source, except: (A) Dronabinol substituted in sesame oil and encapsulated in a soft gelatin capsule in a federal Food and Drug Administration (FDA) approved product, or (B) any THC product that has been approved by the FDA to have a medical use and reclassified in any schedule of controlled substances or unscheduled by the federal Drug Enforcement Administration or successor agency.


This calculation is set forth in Section 21a-240 of the general statutes.


How to Calculate Potency/Concentration


To calculate the potency, or concentration, of a cannabis product, the following formula should be used:


Potency (% THC) = Total mg of THC ÷ Total weight of Product in mg


Both High-THC Hemp Products and Synthetic Cannabinoids are classified as cannabis under State law and may only be sold by licensed cannabis establishments. If you do not hold a cannabis license issued by the Department of Consumer Protection (DCP), it is illegal to sell or offer cannabis, including synthetic cannabinoids and high-THC hemp products. The sale of high-THC hemp products and synthetic cannabinoids at unauthorized retailers is unlawful and action may be taken by law enforcement.


To check if a business has a cannabis establishment license, go to:

Definitions Policies Procedures and The Law Possession Hemp, CBD and Other Products Cannabis use and Safety