Cannabis Learning Center

Reading Labels

Decode THC, THCa, total mg, terpenes, and lab reports.

How to read cannabis labels

A cannabis label is a product’s fact panel. It may include cannabinoids, terpenes, batch number, harvest date, package date, serving size, ingredients, warnings, and lab testing information.

Key label terms

Label itemMeaning
THC %Concentration by weight, usually for flower or concentrates.
THCa %Acidic precursor that can convert toward THC when heated.
Total THCEstimated THC potential, often using THCa conversion math.
mg per servingAmount per edible/capsule/drink serving.
Total mgAmount in the entire package.
TerpenesAroma compounds listed as % or mg.
COA / lab reportCertificate of analysis with batch testing results.

Big mistake to avoid

Do not compare “20% THC flower” and “20 mg edible” as if percent and milligrams are the same unit. Percent is concentration. Milligrams are amount.

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