Interest in learning Korean has spiked since the launch of hit Netflix show "Squid Game, tutoring services reported, underscoring a growing global obsession with South Korean culture from entertainment to beauty products.

Language learning app Duolingo Inc said the nine-part thriller, in which cash-strapped contestants play deadly childhood games in a bid to win 45.6 billion won (US$38.19 million), had spurred both beginners and existing students hoping to...