13. Pakistan
In terms of active personnel, the Pakistani military is one of the biggest in the world. The nation is known to have a sizable fleet of tanks, planes, and attack helicopters. Pakistan is also estimated to be producing nuclear weapons at a rate that, in ten years, could see it own the third-largest nuclear arsenal in the world. Pakistan has a $7 billion per year budget for its military, and is served by 617,000 active workers currently on duty.