How To Pick The Best Computer For You

Liz Thompson   Jul 09, 2019

At 20,000 Leagues Scuba and Aquatics, we are often asked by our Divers why it is so important that every scuba diver have a dive computer with them on every dive. In this blog, we will answer that question, along with offering our views on how to select the dive computer that is best suited to your needs.

Why Dive with Computers?

There are many reasons that a diver might chose to dive with a computer. One of the main benefits of diving with a computer is that it provides you with all of the necessary information- such as no decompression time, safe ascent rate and, in some cases, air time remaining - right at your fingertips. Dive industry information suggests that divers who use dive computers are less likely to have dive-related pressure related injuries and are likely to be more frequent divers.

Computers Types

The first consideration when looking for a dive computer is design. There are four main designs that you might consider. Each design - watch-style dive computer, wrist mounted dive computer, console dive computer, and heads up display – has its own pros and cons.

  • Watch-style computers are the most basic computer. They are casual enough for you to wear as your everyday watch, but they have a smaller screen which can make them more challenging to read while on a dive. Some newer designs such as the Shearwater Teric have bright LEDs that are easily read in any dive and surface conditions.
  • Wrist mounted computers offer a larger display screen than watch-style computers. Wrist mounted dive computers are not directly attached to your dive equipment, which introduces the possibility of loss, however, since it’s not connected, these computers are also helpful to divers who free dive.
  • Another type of computer is the console dive computer, which combines your pressure gauge, computer and compass all into one streamlined console. These computers attach into your regulator via a high pressure hose. Console dive computers also sport a larger display than most watch-style computers. The primary disadvantages are the larger size and portability between regulator sets.
  • The final, and newest, form of dive computer is the heads-up display, or HUD. HUD computers are more expensive than the other types, however they provide the luxury of being completely hands free and enables the diver to enjoy the dive without having to pause to check their wrist or console mounted computers. 

Air Integration

The next consideration is whether to invest in air integration, and if you do, the integration method. Air integrated computers replace a standard gauge to provide a single information system that monitors air supply during the dive. There are two ways to achieve air integration - either through the high-pressure hose or a wireless connection, which transmits information to your computer wirelessly. While wireless transmitters are more expensive, they enable you to streamline by eliminating a high pressure hose. In either case, air integration offers the benefits of being able to monitor depth, no-decompression time, air consumption and remaining air time in a single information display.

Gas Type

Another consideration when selecting a dive computer is nitrox. If you are nitrox certified or intend to become nitrox certified, you will need a computer which is nitrox compatible. As nitrox is a gas mixture with more oxygen that compressed air, it requires computers that have settings to monitor both nitrogen and oxygen exposure as well as calculate no-decompression time and maximum operating depth to offer increased safety during your dives. Nitrox-compatible dive computers also support air dives, offering maximum flexibility to your diving.

Other Considerations

There are other factors that need to be considered when choosing your computer such as log memory size, alarms, the display and screen, and how often the batteries are charged or changed. All these factors should be considered when choosing your dive computer to make sure that the computer meets your specific diving needs.

Our Instructor’s Recommendations

Alan: The Cosmic IQ Deep Blue offers a large color display with Bluetooth capabilities. It is rechargeable which helps to save money on servicing and has a smartphone app that enables storage of your dives in an electronic, internet-based dive log. It is very flexible and reliable.


Marshall: The Shearwater Perdix AI is a computer that grow with you from open water diver to – well, as far as you want to advance as a diver. You have the capability of personalizing with colors, sizes, and screen information to your liking. The computer is compatible with both recreational and technical diving and can be updated over the air using a wireless connection to your phone. And – one of the best features - the AA battery is user replaceable!