Strength

In 1997, with Deep Blue's defeat of Kasparov, computers surpassed human beings at chess. Other games have fallen in more recent years: Go, Starcraft, and League of Legends among them. AI is superhuman at these pursuits, and unassisted human beings will never catch up. The situation looks like this:[1]

At chess, AI is much better than the very best humans

The average serious chess player is pretty good (1500), the very best chess player is extremely good (2837), and the best AIs are way, way better (3700). Even Deep Blue's estimated Elo is about 2850 - it remains competitive with the best humans alive.