A fight in Dragon Ball Super suggests that Krillin is somehow as strong as Android 18 now. Although Krillin is often referred to as the strongest Earthling in the Dragon Ball franchise, it’s long been assumed that every human is below the level of the androids. After all, 17 and 18 were powerful enough to go toe-to-toe with Super Saiyans in Dragon Ball Z.
In Dragon Ball Z, there was a sizable gap between the human characters and the androids. That made sense, considering that there was a time when 17 and 18 were fated to be the death of all the Z-Warriors (including Vegeta and Gohan). Krillin, Yamcha, and Tien tried hard to narrow the distance, but remained several steps behind Goku, Piccolo, Vegeta, and Gohan. When Android 18 switched sides and joined the heroes after the Cell Saga, she was counted as a powerful addition to the Z-Warriors. Her strength also made her a no-brainer for Goku when he was filling out his Universe 7 team. Her ability to outlast dozens of Tournament of Power contenders (and beat Universe 4’s Ribrianne) proved that she’s still a force to be reckoned with.