THE USE OF CHATGPT AND GEMINI AI VOICE ASSISTANT ON STUDENTS’ ENGLISH PRONUNCIATIONAthalla Syafiqa FirryantoRaden CynaraauthorPronunciation is important for English language accomplishment, yet students frequently struggle with segmental components including vowels, consonants, and diphthongs. This research investigates at how two AI-powered voice assistants, ChatGPT and Gemini AI, may help senior high school students enhance their English pronunciation skills. The research, used a quasi-experimental design with pretest and posttest assessments involving two groups of eleventh-grade students from SMA Negeri 2 Bogor. The experimental group used ChatGPT, while the control group used Gemini AI for three treatment sessions. Both tools provided interactive feedback, real-time corrections, and adaptive language input. A quantitative analysis conducted with SPSS, including paired and independent t-tests, showed that both AI tools significantly enhanced students' pronunciation. The findings showed that both AI tools significantly enhanced students' pronunciation. The experimental group's average score got from 60.94 to 75.54, whereas the control group's score got from 60 to 75.69. The independent t-test showed a significant difference (t-value = 3.3212 vs t-table = 1.99444), indicating that ChatGPT was much more effective than Gemini AI. These findings indicate that AI voice assistants, particularly ChatGPT, provide a significant platform for segmental pronunciation enhancement in language learning. Keywords: AI voice assistant, ChatGPT, Gemini AI, English pronunciation, segmental features, pronunciation learningPENDIDIKAN BAHASA INGGRIS2025Universitas Pakuan;Pendidikan Bahasa InggrisThesis