“Fragrances are manufactured in varying concentrations of essential oils in alcohol and other organic solvents, designated in order of increasing concentration as eau de toilette, after shave or toilet water 2-5%; eau de cologne or cologne, 5-10%”

or again “An Aftershave contains less perfume oil (around (1%-3%), therefore the scent isn’t as long lasting as an Eau de Toilette. Many aftershaves contain soothing and cooling ingredients, such as Aloe Vera. This helps soothe the skin after a shave . The alcohol contained will also close skin pores opened by the hot water from your shave. Aftershave will only last for about 2-3 hours so, it isn’t effective if you want your fragrance to last all evening. An Eau de Toilette contains more perfume oil than the Aftershave, typically around 4%-8%. However EDT’s contain too much oil to be put on the face, especially after shaving. You will probably come up all red and blotchy as a result. An Eau de Cologne will contain 2%-5%. Therefore, an Eau de Cologne should be a lighter and not so longer lasting fragrance.”