Base Color for HaircolorQ: How can I know which colors have a blue based color or a violet based color?
A: Generally speaking, when you buy your haircolor and developer separately at the beauty supply stores, you can simply look on the bottles of haircolor and see what the base color is for the color formula. However, this isn't as easy when it comes to prepackaged haircolor kits. In order to make sure of the base color choices you make, this is generally the best way to buy your color. Since the mixing of the color is a simple 1:1 ratio between color and developer.
A good way to help sort things out is to look for keywords that will help you determine the base colors of the haircolor formulas you see on the shelf.
For example, if your color choice is described as cool, then the odds are that it is using a blue, violet, blue-violet, or even red-violet base color, while warm tones often contain red, orange, red-orange and gold base colors. Neutral colors generally use "neutral" color enhancing tones and maintain a cool/warm balance.
Often, you can get help in determining the base color of a haircolor formula by checking the product website. Clairol, L'oréal, and other manufacturers offer online "swatches" and color charts that describe the base color of their product lines. These make a good source if you are looking for information and can't find it from the product packaging or the labeling on the store shelves.
How to color hair
Cool and warm hair colors
The hair color wheel
How to determine the base color of hair coloring products