This study investigates the effectiveness of ChatPDF in assisting English teachers with lesson planning. The research combines both quantitative and qualitative methods, including surveys and interviews with 30 teachers. ChatPDF enables quick information retrieval, summarization, and adaptation of PDF documents, reducing preparation time and improving lesson quality. Results show that the tool enhances time efficiency, accuracy, and flexibility in lesson planning.This study investigates the effectiveness of ChatPDF in assisting English teachers with lesson planning. The research combines both quantitative and qualitative methods, including surveys and interviews with 30 teachers. ChatPDF enables quick information retrieval, summarization, and adaptation of PDF documents, reducing preparation time and improving lesson quality. Results show that the tool enhances time efficiency, accuracy, and flexibility in lesson planning.