The question's a bit ambiguous. Are you talking about the violence inherent in the religion, or the culture that's sprung up around it?
The former can basically be answered by looking at the Koran; the latter is much harder to answer and will get you different answers based on your location.

For the former, Islam is actually somewhat less violent than Judaism (number of times "stoning" is mentioned in the Koran: 0) and about the same as Christianity in the NT only.