Size

• The most obvious difference between a jet boat and a jet ski, upon first inspection, is the size differential. The jet ski usually has only enough room for the driver, but dual-passenger and even three-passenger models exist. Jet boats are much larger in comparison, and can fit several people at once. In fact, most jet boats fit at least two people.
  
  

Power and Agility

• The large size of the jet boat allows more room for a powerful engine. In fact, some of the more powerful jet boats have engines as strong as 1400 horsepower. The large size of the boat compromises agility though. Sharp quick turns are not possible, especially at faster speeds. The jet ski lacks the power of the jet boat, but makes up for it in agility and a lighter design, which enables speeds upwards of 65 mph.
  
  

Functionality

• Some larger jet skis can tow waterskiers or someone on an inner tube. Generally speaking, jet skis are for personal use and function mostly as a personal watercraft. The jet boat's larger size and additional power gives it more functionality. In terms of power, jet boats tow larger loads; and the additional size means more people can fit on board. In fact, in some areas jet boats double as passenger ferries.
  
  

Dangers

• Both the jet boat and jet ski offer safe driving experiences, but the jet ski outnumbers the jet boat in accidents per year. It's hypothesized that the reason for the difference involves operator experience. Since jet skis have more maneuverability, some drivers tend to operate their crafts in unsafe areas; such as between two moving boats or over wakes. These situations can easily cause crashes for an operator with little experience. Operators of both crafts perform better after extensive experience.