Garmin Descent X50i, Premium Dive Computer

They're built for different divers. The X50i is Garmin's large-format dedicated dive computer: a 3-inch color touchscreen with sapphire lens, DiveView maps with bathymetric contours, an integrated backup dive light, and a 200-meter rating — a big, glanceable instrument worn over a wetsuit. The Mk3i is the dive computer you wear as your everyday watch: same 200-meter rating and T2 air integration, but in a 43mm or 51mm smartwatch with health tracking, music, and Garmin Pay. Choose the X50i for maximum in-dive readability, the Mk3i if you want one device on your wrist all day.

No — the X50i is designed as a dedicated dive computer, not a daily smartwatch. It covers diving, DiveView maps, compass, weather, and phone notifications, but it does not include Garmin's health and fitness tracking, sports apps, music, or Garmin Pay. If you want full smartwatch features plus a true dive computer in one device, that is the Descent Mk3i's job.

The X30 is the entry point to Garmin's large-format line: a 2.4-inch button-operated color display, 10 ATM rating, up to 30 hours of dive battery, and full multi-gas support. The X50i steps up to a 3-inch touchscreen with sapphire lens, a 200-meter rating, T2 air integration with monitoring for up to 8 divers, SubWave diver-to-diver messaging, DiveView bathymetric maps, and an integrated backup dive light. One honest note: the X30's simpler display actually gives it longer battery life per charge — what you're paying for in the X50i is the screen, the air integration, and the mapping.

Yes. Pair a Descent T2 to your tank and the X50i shows tank pressure, air time remaining, and consumption rate. It can monitor up to 8 divers using T2 transceivers within about 10 meters — pressure, depth, and distance for each — and exchange preset diver-to-diver messages up to 30 meters through Garmin's SubWave sonar network.

In dive mode, Garmin rates the X50i at up to 13 hours at high brightness, up to 16 hours at medium brightness, and up to 20 hours in Night Dive mode per charge — comfortably a full liveaboard day of repetitive diving between charges.

A dive computer tracks the actual depth and time profile you have dived and the tissue loading that follows from it, which is personal to you. A rented computer has no record of your recent diving, and swapping models each trip means relearning the display and menus when you should be focused on the dive. Owning one you know well is a genuine safety and comfort improvement.

No. A computer only tracks the profile of the diver actually wearing it, and even buddies who stay together do not follow identical depth and time profiles. Every diver needs their own computer, and passing one between divers or between dives is unsafe.

Conservatism settings make the computer's calculations more cautious, shortening allowed bottom times and adding margin beyond the base algorithm. Divers commonly add conservatism for factors such as cold, hard work, fatigue, or repetitive multi-day diving. How and when to adjust it is covered by your training and your computer's manual, so set it before you get in the water and follow what your computer tells you during the dive.

Broadly there are two types: user-replaceable batteries, often a coin cell that you or a shop swap along with resealing an o-ring, and sealed rechargeable batteries that charge from a cable or dock. Neither is universally better, as replaceable cells are convenient on remote trips while rechargeables avoid ever opening the case. Follow the manual exactly for any battery change, because an improperly seated o-ring or case is the usual cause of a flooded computer.

Yes, both change the picture, and both are governed by your training agency's guidance and your computer's instructions rather than any casual rule of thumb. Many computers have an altitude setting that must be configured before diving at elevation, and most display a no-fly or surface-interval countdown after a dive. Follow your computer and your training, and ask a dive professional or a dive-medicine specialist if you are unsure.

Rinse it in fresh water after every dive day, paying attention to the buttons and around any sensor openings where salt crystals form, and let it dry fully before storing. Keep it out of prolonged direct sun and extreme heat, and avoid pressing buttons while sand is on the case. Inspect the strap or bungee often, because a failed strap loses far more computers than a failed computer does.

A wrist computer is worn like a watch and read by raising your arm, while a console computer sits at the end of a hose with your other gauges. Air integration means the computer also displays cylinder pressure, either through a hose or from a wireless transmitter on the first stage, and often estimates remaining gas time. All of them run a decompression algorithm, so the real difference is where you read the information and how much of it you get.

The Descent X50i carries a 200-meter rating, the same as Garmin's flagship Descent Mk3i watch. That covers recreational, technical, and deep diving with a wide margin. It is a step up from the Descent X30, which is rated to 10 ATM.

Yes. The X50i includes DiveView maps with bathymetric contours, so you can see underwater topography rather than just a coastline. It also carries a compass, weather, and phone notifications. Mapping is one of the main things you are paying for over the button-operated Descent X30, which does not have it.

Yes, the X50i has an integrated backup dive light built into the unit. It is intended as a backup rather than a replacement for a proper primary torch, but it means you always have a light on your wrist. Paired with the X50i's Night Dive display mode, it makes the computer noticeably more useful after dark.

The X50i has a 3-inch color touchscreen protected by a sapphire lens. That is the largest display in Garmin's dive lineup and the reason the X50i exists: it is a big, glanceable instrument meant to be read at arm's length over a wetsuit, not a watch you wear to dinner. The Descent X30 uses a smaller 2.4-inch display operated by buttons instead.

Yes. The X50i has a dedicated Night Dive mode that dims the big display, and Garmin rates the battery at up to 20 hours per charge in that mode compared with up to 13 hours at high brightness. It also has an integrated backup dive light, so you have a light source on your wrist if your primary torch fails.

Both are dedicated big-screen dive computers rated to 200 meters with a built-in light, so the decision comes down to air integration and battery. The X50i gives you Garmin's T2 transceiver support with monitoring of up to 8 divers, SubWave diver-to-diver messaging, DiveView bathymetric maps, and up to 13 to 20 hours of dive battery per charge. The Nautic has a larger 3.26-inch AMOLED, Buhlmann 16 GF with adjustable gradient factors, Suunto Tank POD support for up to five cylinders including sidemount, and a much longer battery at up to 120 hours of dive time. Choose the X50i for the Garmin dive ecosystem and buddy monitoring, the Nautic for battery life and gradient-factor control.

They are different shapes of dive computer. The G2 is watch-sized, with a 1.2-inch AMOLED touchscreen, a 100-meter rating, no air integration, and full Garmin smartwatch features including Garmin Pay and health tracking, so it doubles as your daily watch. The X50i is a large-format instrument with a 3-inch touchscreen, a 200-meter rating, T2 air integration, DiveView maps, and a backup dive light, but it deliberately leaves out the fitness and smartwatch side. Buy the G2 if you want one device on your wrist all day, the X50i if you want maximum readability and tank pressure underwater.