Duolingo is a platform on which users can learn over 40 languages, such as English or Spanish, free of charge.
DUOLINGO WEBSITE
DUOLINGO'S IG
Luis von Ahn's twitter
APP STORE
UNSPLASH
The bulk (~ 90%) of the revenue that Duolingo generates comes from a premium subscription called Plus.
DUOLINGO WEBSITE
Users on the free tier occasionally see ads, which appear within the progress board, between lessons, and within your profile.
IMAGE VIA CANVA
In 2014, Duolingo launched online language proficiency tests that cost $49 per taken exam.
DUOLINGO ENGLISH TEST WEBSITE