A dive computer, personal decompression computer or decompression meter is a device used by an underwater diver to measure the time and depth of a dive so that a safe ascent profile can be calculated and displayed so that the diver can avoid decompression sickness.

A dive computer, also known as a personal dive computer, is every diver’s underwater best friend. It’s a device that usually takes the form of a small square console or a watch and is used to keep track of the details of a dive in order to help divers avoid a serious condition called decompression sickness or “the Bends” 

As you may already know, decompression sickness is caused by a rapid and dangerous build-up of nitrogen bubbles in the body when the diver doesn’t properly pace themselves as they swim to the surface.

Dive computers assist divers to safety by helping them monitor and keep nitrogen levels within safe limits. They automatically measure the time and depth of each dive and then create a safe ascent profile based on that information. They also calculate the gases in the body to track the dissolved nitrogen and display the diver’s No Decompression Limit (NDL), which tells them just how much dive time they have left based on their dive profile.

These gadgets are incredibly convenient for divers—not to mention potentially life-saving. Aside from reducing the need to carry a separate gauge and watch to measure the dive depth and time, it is able to warn divers about missed decompression stops and helps them regulate their ascent rate.