The caffeine content of a beverage is measured by inserting a dipstick into the beverage. The dipstick is impregnated with a reagent that changes color when reacted with caffeine. The degree of color change will be proportional to the concentration of caffeine in the beverage. The dipstick may be provided with a graded color chart which can be compared to the color of the dipstick so as to ascertain the concentration of caffeine in the beverage. The dipstick will preferably include a beverage dipping section; an adjacent temperature moderation section; and an adjacent reagent-impregnated section. The beverage is preferably wicked from its container to the reagent-impregnated section of the dipstick. In this manner, the reagent is never directly admixed with the beverage in the container.