By September 2015, approximately 110 million people were using Duolingo to learn English. The most recent total number of English learners on Duolingo is obtainable at any time by adding up the users of all English courses.
In June 2015, a company spokesman of Duolingo revealed that the language learning app passed the milestone of 100 million users. By September 2015, however, these numbers had already greatly increased, with 45.5 million Spanish speakers, 18.9 million Portuguese speakers and 6.9 million French speakers making the largest groups of English learners. The smallest groups of English learners on Duolingo are the Ukrainian speakers, consisting of 127.000 learners. An earlier study also showed the relative numbers by outlining percentages for the languages that are studied, with English being the most popular language studied by 44.5 percent of Duolingo users.