Hair colour charts make us want to do crazy stuff to our hair. That aside, when we are looking at hair dyes, they usually have a code and description to give us an idea of how dark it is (the depth) and what colours are in the finished colour (the tones). While many manufacturers use their own in-house system, there is a global numbering system to create a more precise definition of hair colour. It’s called the International Colour Chart, which uses numbers to convey what the depth of the colour is, and what tones (if any) are in the colour.
What is the International Colour Chart?
The International Colour Chart (ICC) is a numerical system used worldwide to classify hair colour. It means that each hair colour has a definition that is recognised around the globe, and can be used by manufacturers on hair colour charts and tubes/boxes of hair dyes.
Each hair colour is given a number, which tells us two things: firstly, the depth (also called level) and, secondly, if there are any tones in the colour.
The depth/level number is usually separated from the tone number by a dividing symbol like a decimal point, a slash or a hyphen – for example: 4.6, 4/6, 4-6 all say the same thing as far as the ICC go (“a medium brown base with a warm red tone”).
Not all hair colour manufacturers use the ICC – some have their own in-house numbering system, like using letters to represent the different tones e.g. R for red, or M for mahogany.
Also, even if a manufacturer is using the ICC system, colours from brand to brand can vary; so one brand’s 4 (“medium brown”) can be different to another brand’s 4.
It’s not perfect, but the ICC goes a long way to standardising how we define hair colouring products.
How Depth and Tone are Numbered
Depth or Level
Depth is given a whole number from 1 to 10, where 1 is the darkest hair colour (black) and 10 is the lightest (lightest blonde). Some manufacturer’s also use 11 and 12 on their colouring products to account for the blondest of the blonde. As you can see in the picture below, numbers 1-5 are browns, and 6-10 are blondes:
Tones are numbered from .0 to .9.
Hair colouring products can have just the base colour without any tones, or they can have up to three tones in it, though one and two tones are most commonly seen.
The first number given for the tone is the primary tone, and the second number is the secondary tone. The primary tone has more influence over the final colour than a secondary tone.
For example, as shown in the picture above, an 8.1 is a light blonde with a cool ash tone. 8.13 is also a light blonde with a cool ash tone, but the final colour also has a hint of warming gold in the background.
Zero is used to indicate how intense a tone is. For example, a 4.06 is a medium brown with just a hint of red, creating a warm coffee colour, while a 4.60 is medium brown with a more definite and obvious red tone to the hair (more than a 4.6 would have).
Double tone means a greater intensity and vibrancy of that particular tone, so a 4.66 means a strong red tone on medium brown hair.
Mahogany (a mix of red and purple) is normally used with another tone in hair colour, rather than just on its own. Mahogany itself is neither warm nor cool – the tone it’s paired with determines whether the final hair colour is warm or cool. For example, a 4.15 (chocolate brown) is a cool colour; whereas a 4.56 would be a warmer colour.
|ICC Number||Tone||Actual Colour||Cool or Warm|
|.x0||–||–||Depends on primary tone|
Hair Colour Charts
Each manufacturer lays out their hair colour charts differently, though they are generally logical and organised into tonal groups (like mahogany, red or ash).
Below are some examples of hair colour charts to see how they are laid out and how the ICC is used. Click on the hair colour charts to go large.
So, that’s our look at colour charts for hairdressing. The temptation to dye is strong. Resistance is futile!