A question we see asked frequently is "How do CS:GO ranks work?" - well, we’d all like to reach Global Elite one day, and while it’s clear that winning games and getting headshots is a pretty good way to do so, the lack of a transparent MMR and the complexity of five-man teams makes the system pretty complicated. Can you game it? Probably not, but the community did manage to unearth a few interesting data points over time.
CS:GO’s matchmaking system is a heavily modified example of the GLICKO-2 rating system. While not many details are known of the changes Valve made to the original algorithm, it’s important to know that the original GLICKO-2 features rating deviation and volatility calculations beyond just looking at an MMR number.
Supposedly, the specific number of rounds won and MVP stars also play a part in the calculations, which is why indiscriminate frag-hunting in games you dominate actually can be a good idea. (By the same token, minimizing the number of lost rounds could be just as important, if not more!)
Non-competitive game modes no longer use any kind of a matchmaking system, simply grouping players based on their ping. Hopefully the above answers the question of "How do CS:GO ranks work?" - hopefully you go on to reach the dizzying heights of Global Elite!