This study evaluated the reading and listening proficiency levels of 245 English language learners who completed the Basic content (through Common European Framework of Reference for Languages [CEFR] level A2) of one of the following three Duolingo English courses: English for Japanese, Spanish, or Portuguese speakers. Participants self-reported having little to no prior proficiency in English and used Duolingo as their only learning tool. Their language skills were measured using the reading and listening sections of the STAMP 4S English Test from Avant Assessment. The results show that, on average, learners at the end of the Basic content (A2) scored Intermediate High in both reading and listening in all three courses. Given that Duolingo's English courses are CEFR-aligned with an expected proficiency outcome of Intermediate Mid upon completion of the A2 content, it is noteworthy that participants across the three studied courses surpassed these expectations by achieving an additional American Council on the Teaching of Foreign Language (ACTFL) sublevel in both reading and listening. Such results present a robust and coherent body of evidence affirming the efficacy of Duolingo's English courses in enhancing learners' competencies in reading and listening comprehension.