The answer to this question depends on a number of factors, but most black dyes fade within four to six weeks after they have been applied. This is because permanent black hair dye is water-soluble, meaning that a layer of pigment strips away the strands every time you wash your hair.
If you’re using a demi- or semi-permanent color, the fading process will start sooner than in case of a permanent dye because the latter is more harsh on your hair. This is because the oxidation used in the dying process can damage the hair and cause it to break down.
In addition to the type of dye, other factors will also contribute to how quickly your color fades, such as how often you wash it and your hair care routine in general. For instance, you should use sulfate-free shampoo and conditioner that are specifically designed for colored hair to help seal in the pigment and prevent it from fading.
You should also avoid excessive exposure to the sun, as UV rays can strip the pigment from your hair and make it fade more rapidly. In addition, you should try to avoid using hot tools (such as curling irons and straighteners) since these can open the cuticles of your strands and strip them of their color.
If you’re interested in dyeing your hair black, we recommend choosing a shade that is flattering to your skin tone and complements your natural color. For example, a warm brown-black will look beautiful on fair complexions while a rich dark brown or violet-black will be better suited to darker skin types.
