There are so many shades of natural hair color. A brown can be light or dark, have subtle undertones of red or lean toward a deep, almost black shade. Same with blondes and reds. So, when it's time to color your hair, you first select a color; and these colors are pretty standard:
Level 1: Black
Level 2: Darkest (almost black) brown
Level 3: Very dark brown
Level 4: Dark brown
Level 5: Brown
Level 6: Light brown
Level 7: Dark blond
Level 8: Medium blond
Level 9: Blond
Level 10: Light blond
But next, you need to determine the tone of the hair color you select. So, how do you determine the tone of the color.
Your skin tone (basically the color of your skin) tells you what tone your hair color should be.
Your skin tone contains underlying pigments. If you were born with black or brown hair, you will likely have warmer, earthy undertones in your skin like orange, brown, gold or orange-based red. If you were born with blonde hair, you probably have cooler skin undertones like blue, green, pink or blue-based red.
Hair color tones generally fall into three standard categories: warm, cool, and neutral. When hairstylists discuss color, or if you are choosing a color from a swatch book, the tones are often indicated with a letter. Here are examples of standard color tones:
Cool TonesA: Ash
N: Neutral—neither warm nor cool
Those with warmer undertones in their skin will look better with a warmer hair color, like golden blondes or honey browns. Conversely, those with cooler undertones in their skin will look better with cooler hair colors, like ash blonde, black or auburn brown.
Generally the makeup you are using should already tell you if you are a warm- or cool-toned person. But if you are unsure, look at a vein in your arm under natural light. If it appears green, then you have warm tones, if it is blue then you have cool-toned skin.
Be aware that your skin tone changes as you age. Right before you turn gray, the hair gets a little darker. Your skin is preparing to lose pigment as you age. Then, when your hair turns gray, your skintone gets lighter.