Massachusetts Board of Cosmetology Practice Exam 2026 - Free Cosmetology Practice Questions and Study Guide

The most permanent type of hair dye is a permanent color. Permanent hair color penetrates the hair shaft and alters the color of the hair by opening the cuticle layer. This allows for longer-lasting results, as the color is less likely to wash out compared to other types of hair color options. Permanent hair dyes typically contain ammonia and a developer, which help to ensure that the color remains vibrant and resistant to fading over time.

In contrast, semi-permanent color does not contain ammonia and generally lasts for a shorter duration, gradually fading after several washes without significantly altering the hair’s natural pigment. Temporary color, as the name suggests, is designed for short-term use and can be easily washed out after a few shampoos, sitting on the hair surface rather than penetrating. Demipermanent color is also less permanent than traditional permanent color since it doesn’t fully lift the natural pigmentation and tends to fade more quickly, usually lasting through about 20 to 28 shampoos. These differences highlight why permanent color is the most enduring option available for hair dyeing.