Potency is how much of each cannabinoid a product contains. It is the number most people look at first, especially total THC, but it is only one part of the story.
Potency is shown in two main ways. Percentage (%): used for flower, pre-rolls, concentrates and carts. It tells you what portion of the product's weight is a given cannabinoid. 20% total THC means about 200 mg of THC per gram. Milligrams (mg): used for edibles, tinctures, beverages and topicals. It tells you the amount per serving and per package.
Typical ranges: flower often falls around 15-30% total THC, while concentrates and carts often test from 60% to over 90%.
Higher potency is not automatically better. It means more THC per amount, so you need less. Many people enjoy moderate-potency products more. Terpenes, freshness and your own tolerance shape the experience a lot.
Potency results come from lab testing and can vary between labs and samples. Use them to compare products and to dose carefully, and check the COA to see how they were measured.