In this paper we present the results of a study carried out at the University of Sharjah (UOS) over the past three semesters to evaluate the impact of online exams on the performance of students and examines student perceptions, attitude and feedback on online assessment in comparison to traditional in-class exams. The study (1493 respondents) aims to answer questions on effectiveness and impact of online assessment, especially those related to time management, preparation, reliability, fairness, security, grading, prompt feedback and possible impact on students’ performance. The survey also aims at identifying possible risks associated with online assessment at the UOS. The results indicate that there is no clear indication of improvement in the overall class GPA or in the overall passing percentage of the class. Student’s opinion and perception on online assessment seem to be divided among the 1493 students who responded to the online survey. More than half of the students preferred online exams over traditional paper-based exams. Students’ opinion was more in favor of online exams in questions related to the added values and benefits of online exams, especially those related to logistics and improving teaching and learning. No age or gender biases were found in any of the areas investigated. The results of our study support the UOS’s effort to integrate online summative assessments into teaching and learning, which will in turn improve the quality of education through accurate and fair assessment. UOS need to raise awareness among staff and students on the values of online testing in improving course assessment and help facilitate testing logistics.