What is the measurement system that colorists use to determine the lightness or darkness of hair color?

The level system is the standard measurement used by colorists to assess the lightness or darkness of hair color. This system categorizes hair color on a scale that typically ranges from 1 to 10, with 1 representing the darkest black and 10 signifying the lightest blonde. Each level corresponds to a specific shade, enabling colorists to identify a precise hue and make accurate adjustments to achieve the desired color result.

Using the level system is essential for color formulations, as it helps in determining how much lift is needed or how to balance various tones. This system allows for clear communication between colorists and clients regarding the expected results, ensuring a consistent understanding of color expectations during the coloring process.

In contrast, while the color wheel offers a visual representation of color relationships and the shade catalog provides a collection of available colors, these tools do not measure lightness or darkness directly. The brightness scale, while applicable in some contexts, is not specifically utilized to indicate the levels of hair color in the same structured manner as the level system.