https://www.gamespot.com/articles/pubg-passes-3-million-concurrent-users-on-pc/1100-6455835/

PUBG is one of the biggest games on the planet and it continues to grow. On December 30, the Hunger Games-like shooter passed 3 million concurrent players on Steam. That's up from 2 million at the start of October and 1 million peak concurrent users in September.

Playerunknown himself, Brendan Greene, has said he thinks the game could reach 100 million players to achieve League of Legends-like success. Three million is more than four times the number of the second-most popular game on Steam, Dota 2, which had around 705,000 concurrent users on December 30. It's down today, January 2, as the game had around 2.79 million concurrent players, according to Steam's own public stats.