Milligrams per milliliter

Milligrams per milliliter is a concentration unit that states how much of a substance is dissolved in each milliliter of a liquid product.

The figure is calculated by dividing the total milligrams in a bottle by its volume in milliliters. Two bottles can contain the same total amount at different concentrations if their volumes differ, and two bottles of the same volume can differ greatly in strength. Concentration matters because a dropper delivers volume, not milligrams, so the amount in a given volume depends entirely on this number. Laboratory certificates of analysis for liquids report potency in the same unit.

CBD oils and tinctures commonly display the total milligrams prominently while the concentration appears in smaller print or must be worked out from the label. Reading both figures, along with the stated dropper volume, is how a reader understands what a product contains. The unit describes composition only and carries no implication about absorption or effect. It is also used on veterinary products and in pharmacokinetic research when describing the preparations studied.