What is the difference between temporary and permanent hair color?

The distinction between temporary and permanent hair color lies fundamentally in their formulation and the way they interact with the hair. Temporary hair color generally utilizes direct dye molecules that do not penetrate the hair shaft deeply; instead, they coat the outer layer of the hair and can easily be removed with shampooing. Typically, temporary color can last for about a few washes—often just a handful, making it ideal for those looking to experiment with color without a long-term commitment.

On the other hand, permanent hair color involves a chemical process that alters the hair structure. This type of color penetrates the hair shaft and interacts with the hair's natural pigment. Permanent color lifts the hair's original color and deposits the new shade, resulting in a lasting change that can only be reversed by the natural growth of the hair or by further chemical processing. Thus, the ability of permanent color to change the hair structure and provide long-lasting results differentiates it significantly from temporary color options.