The rapid expansion of online learning has transformed assessment practices in higher education and K–12 institutions worldwide. Online assessment methods offer flexibility, accessibility, scalability, and immediate feedback, making them essential components of contemporary digital education. However, concerns regarding academic integrity, cheating, plagiarism, identity verification, and assessment security remain significant challenges. This study investigates the effectiveness of online assessment methods and examines factors influencing academic integrity in virtual learning environments. A mixed-method research design involving 850 students, 220 faculty members, and 60 academic administrators was employed. Quantitative survey data and qualitative interviews were analyzed to evaluate perceptions of online assessments, integrity concerns, technological solutions, and institutional policies. Findings indicate that while online assessments enhance flexibility and student engagement, academic dishonesty remains a major concern. Effective assessment design, technology-based monitoring systems, ethical education, and institutional support are critical for maintaining academic integrity. The study proposes a comprehensive framework for secure and effective online assessment implementation.