Abstrak
The purpose of this study is to determine whether there is a significant difference in English vocabulary among class VIII students at MTs DDI Tarakan who use Duolingo apps. This study used a quantitative method using pre-test and post-test experimental designs. The subjects in this study were eighth-grade students. The sampling technique utilized was purposive sampling, which involved sampling the entire population, hence the sample size was 17 students Data collection included vocabulary pre- and post-tests, as well as interviews. The results indicated that the hypothesis was accepted. The sample t-test showed a significant (2-tailed) result of 0.000 0.05. If the two-tailed significance level is less than 0.05. Based on pre-and post-test data, the researchers discovered a substantial relationship between Duolingo use and students' English vocabulary. Students' vocabulary improves significantly after using Duolingo Apps. Students enjoyed the learning process and improved their vocabulary understanding and retention, indicating Duolingo's effectiveness for English vocabulary among MTS DDI Tarakan grade VIII students.