Iowa Cosmetology Practice Exam 2026 - Free Cosmetology Practice Questions and Study Guide

The purpose of a filler in hair color is primarily to neutralize unwanted tones. When hair has been previously colored or lightened, it can often develop undertones that are not desirable, such as brassy or overly warm shades. A filler helps to restore the balance of color by depositing a base color that can counteract these unwanted hues, providing a more even and harmonious overall result. This is particularly important when working with blonde shades, as they can easily exhibit unwanted yellow or orange tones after bleaching. By using a filler, the stylist can achieve a more aesthetically pleasing outcome and ensure the hair color turns out as intended.

The other possible purposes mentioned do not accurately define a filler’s role in hair color application. For instance, while shine can be added through certain treatments or finishing products, fillers specifically contribute to color balance rather than shine. Enhancing curl pertains to styling products and techniques rather than color correction, and increasing volume is typically the function of volumizing products or specific hair cutting techniques, not related to coloring processes.