Valve does not officially make it known to the public exactly how player ranking in Counter-Strike: Global Offensive (CS: GO) is calculated. The only known information is that for Competitive modes, Valve built a specific system for CS: GO that is significantly more complex than Elo.

What Is the Elo System?

The Elo rating in video games is inspired by a system developed by the Hungarian-American physics professor, Arpad Elo. Applied in competitive gaming, the Elo rating system allows the game to assess in a fair way the skills of the players. These players are then matched based on their ratings. With this, players are more or less equal in skill for every match made.

The CS:GO competitive ranking system, however, uses the ideas based on the Glicko-2 rating model. Glicko is an improvement over the Elo system. The Glicko-2 rating model used in CS:GO is altered since its inception to fit CS:GO players and their skills. Computations are based on matchmaking parameters through a scientific set of rating variables. These variables are represented as Skill Group. There is a lot of deviations and volatility in these scientific sequences in this system that it is hard to pin down how it works.

What Is Profile Rank?

For the purpose of this guide, "rank" means Skill Group and not the Profile Rank. Profile Ranks were introduced in the Operation Bloodhound update back in 2015 and are mostly cosmetic, not affecting competitive matchmaking at all.

By playing games on the official CS: Go servers, players gain experience points that increase their Profile Ranks. Players gain more experience depending on the season. Leveling up Profile Ranks gives a chance of receiving weapon crates drops.