No, a physical calculator cannot be used during the CAT exam. An on-screen, digital calculator is provided for the candidate which can be operated. However, the software of the exam is such that the individual is better off not using the same as it is slow and leads to time wastage. As everyone must have heard, this exam is about smart work and tests the aptitude of an individual. Hence, if the concepts are clear and an individual uses the right shortcuts to solve the questions, detailed calculations are not required. Since the exam is relative and attempting every question is not necessary, questions to be attempted should be chosen in such a manner that avoids large calculations and can be quickly solved with minimum effort. Time is of importance here and if 2 easier questions can be solved instead of one complicated one, the former should be preferred as positive and negative marking is standardized for each of them. There is also a risk in attempting complicated questions as the candidate might recheck the process of arriving to be reassured.