Choose Foundations Using The MAC Cosmetics Shade Guide

From experience I can tell you that finding the correct foundation shade can be difficult.  I have, in the past, ended up with the wrong foundation shade or wrong undertone.
After lots of research, last year I found out that I can choose the correct foundation and undertone just by knowing my MAC foundation shade.  There are a few websites or blogs that explain this as well.
I am NC30 in MAC terms.  This is my shade most of the year, I do tend to get slightly lighter in winter.
So I am going to try my best to explain what I have learnt just by knowing my MAC shade.

When getting color-matched at MAC, you could be told that you are one of the following :
C, NC, N, NW, and W.

Shade C  =  "Cool"
Match for : Yellow-Golden Olive Skin (warm undertone)

Shade NC  = "“Neutral Cool”
Match for  :  Golden Beige Skin  (Warm undertone)

Shade N  = “Neutral”
Match for : Beige Skin  (Mix between pink and yellow)

Shade NW =  “Neutral Warm”
Match for : Pink Beige Skin  (Cool undertone)

Shade  W  = “Warm”
Match for :  Pinkish Skin  (Cool undertone)

The number that follows the letter(s) denotes the depth of the shade. The higher the number, the deeper the color. For instance NW55 is a match for very dark pinkish beige skin, whereas NC20 would be a match for somewhat lighter, golden beige skin.

The problem that people have when understanding MAC shades is that MAC name their shades opposite to their meanings.   So this is what you need to remember:
NC is for a warm / yellow undertones yet NC stands for Neutral Cool.
NC = Not Cool --> therefore it is warm (yellow undertone)
NW is for cool / pink undertones yet NW stands for Neutral Warm.
NW = Not Warm --> therefore it is for cool (pink undertones)
Similarly C is for warm / yellow skin-tones and W is for cool / pink skin-tones.

MAC foundations like Studio fix Fluid are labeled with NC or NW coloring,  while foundation like Mac Face & Body is labeled C or N.  Matchmaster foundation follows a different numbering system.

Lots of people do not know their shade or undertone.  So even if you want to buy another foundation from another brand, it would be worth your while getting colour matched at a MAC counter first because then you will know your shade and undertone.  I always google a foundation shade against my MAC shade before I buy a foundation from a different brand. Eg.  in the search engine I would type "Revlon Colorstay Mac NC 30"  The results will come up as "008 Golden Beige".  I have bought a few foundations from other brands with the correct undertone and shade by using this method.  I also know which lines do not carry warm / yellow undertone foundations so that I know to stay away from them.

I hope that you found this useful like I did.  Please leave any questions you may have in the comments section below.

Thank you for reading
XOXO.