This conceptual paper describes the comparison between flipped learning and flex model in the classroom. It is different from traditional approach where teachers/lecturers give the lecture first followed by exercises in the classroom. This paper has been divided into several categories such as flipped learning, flex model, the advantages and disadvantages of flipped learning, the advantages and disadvantages of flex model, how to learn English using flipped and flex model and followed by conclusion. By doing the comparison, this paper shows the most comprehensive teaching style where it would help the teachers/lecturers to implement in their teaching. From the comparative study, it can be seen that flipped model is suitable to use in ESL classroom as the students are not necessarily go to the Language Lab to learn English. Activities also can be done in the classroom itself. Students watch the video prior to the lesson and discuss about the lesson or do some activities in the classroom according to the topic given. It will save time both teachers and students as they can focus more on problem-solving activities rather than listening to the lecture. Teachers can monitor students’ performance during class activities and they can also facilitate and help the weak students. As this research not covering all 4 main models of blended learning, future research can be focused at the whole model of blended learning from various aspects.