The Almost Perfect Recreational Dive Computer

The Suunto D5 has been around for a few years now, which in dive computer years is ancient. In an era where Garmin and Shearwater are pushing out new models every 12-18 months, the D5 has remained largely unchanged. That is because Suunto got a lot right the first time. After 50+ dives using it as my primary wrist computer, here is my honest assessment.

Display - The D5 Best Feature

The 1.2-inch color AMOLED display is beautiful. Colors are vivid, text is sharp, and the backlight is bright enough to read in pitch-black night diving conditions. The screen is always on and does not require a wrist gesture or button press to activate. Out of the water, it looks like a premium smartwatch display - friends who did not know it is a dive computer often asked what watch I was wearing.

The user interface is intuitive. Five buttons around the bezel control everything, and the menu system is logically organized. Setting up nitrox mixes takes about 15 seconds. The display layout during a dive shows depth, time, no-deco time, temperature, and tank pressure (with the optional transmitter) in a clean, easy-to-scan format.

The downside: the Gorilla Glass bezel is scratch-prone. After 50 dives, including regular boat deck use, my display has micro-scratches. They are only visible in direct light at certain angles and do not affect readability underwater, but it is something to be aware of. A screen protector is highly recommended.

Dive Performance and Algorithm

The D5 runs Suunto RGBM (Reduced Gradient Bubble Model) algorithm. This is a conservative algorithm that errs on the side of safety. If you are used to Suunto computers, you will feel right at home. If you are coming from a more liberal algorithm like Buhlmann ZHL-16, you may find the Suunto no-deco limits frustratingly short, especially on repetitive days.

The built-in compass is excellent. It is tilt-compensated and responds quickly, with bearing markers that are easy to follow. The compass rose can be displayed on the dive screen simultaneously with your depth and time data. During training dives, I used it for basic navigation drills and it performed perfectly.

Tank pressure integration via the optional Suunto Tank POD works well. The wireless transmitter pairs easily and updates pressure in near-real-time. Battery life on the Tank POD seems to be about 6-8 months of regular diving.

Dive Modes

The D5 supports Air, Nitrox (up to 99% O2), Gauge, and Free Diving modes. For recreational divers, this covers everything. The Free Diving mode logs depth, time, surface intervals, and even provides ascent rate warnings. The nitrox support is straightforward - set your mix percentage and the computer adjusts automatically.

What you do not get: trimix support, CCR mode, or multi-gas tech diving features. This is a recreational computer. If you are diving beyond 40 meters on mixed gases, look at the Suunto Eon Core or a Shearwater Perdix.

Battery Life and Connectivity

The internal lithium-ion battery lasts about 10-14 days with daily dive use and moderate smartwatch features (notifications only, no HR tracking). Recharging is via the proprietary magnetic USB cable, which snaps onto the back of the watch. It is one more cable to travel with, which is annoying, but the charging process is quick - 0 to 100% in about 2 hours.

Bluetooth connectivity to the Suunto app works well for downloading dive logs and updating firmware. The app is functional and displays dive profiles with decent detail. It is not as polished as Garmin Dive or Shearwater Cloud, but it works.

The Smartwatch Problem

The D5 tries to be a smartwatch with phone notifications, step counting, and activity tracking. It fails at this. The notification support is basic - you can see message previews but cannot interact. The step counter is inaccurate compared to any fitness band. The activity tracking covers only basic modes. The smartwatch features feel like an afterthought. Buy the D5 as a dive computer that happens to show notifications, not as a hybrid smartwatch.