This chart from Statista compares the military might of the South and North Korea. While the number of troops is higher for North Korea including their preparedness for battle; South Korea compensates with latest technologies and advanced weapons.

What really tips the balance is not shown in the chart. North Korea is a nuclear-powered nation, while South Korea isn't. 

A military conflict in the region could result in a dangerous devastation for everyone involved. Tensions in the Peninsula reached heightened levels as the US President sends powerful armada in the Korean waters to neutralize threats from the North.