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Garmin Descent Mk3i 51mm Dive Smartwatch

by Garmin
Original price $1,599.99 - Original price $1,799.99
Original price
$1,599.99
$1,599.99 - $1,799.99
Current price $1,599.99

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Descent Mk3i 51 mm

Garmin Descent Mk3i 51mm Dive Smartwatch

The Garmin Descent Mk3i 51mm Dive Smartwatch is a dive computer with a 1.4-inch AMOLED display and an LED flashlight that works above or below water, weighing 105.6 g on its silicone band. Dive mode lasts up to 66 hours, or up to 40 hours with air integration through Descent T2 transceivers (sold separately) paired to the watch. You can log every dive with its surface GPS entry and exit points and look back over it in the Garmin Dive app. Carbon gray DLC titanium comes on a black silicone band or on a DLC titanium band.

The Garmin Descent Mk3i is an air-integrated dive computer and GPS smartwatch built for deep, connected exploration. With a bright 1.4-inch AMOLED display, 200-meter dive rating, sapphire lens, and inductive metal buttons, it's built for technical diving and extreme durability. With SubWave sonar technology and up to 8 Descent T2 transceivers (sold separately), you monitor tank pressure and send diver-to-diver messages. Those transceivers also let you keep track of your dive team, all without surfacing. Messages between divers are supplemental and should not be relied upon as a method to receive emergency assistance. DiveView color maps, multi-gas dive modes, surface GPS, and a personalized Dive Readiness Tool help you prepare for every dive.

Out of the water, the Mk3i moves into your daily life with multisport training, smart notifications, music storage, Garmin Pay, and health tracking features like VO2 max, Pulse Ox, sleep monitoring, and Jet Lag Adviser. The notifications come through when paired with your compatible smartphone; music subscription may be required. Preloaded topo, ski, and golf maps plus turn-by-turn navigation make it your go-anywhere adventure companion. It carries a full set of smartwatch features.

DISPLAY
1.4 in.
454 x 454 AMOLED touchscreen
DIVE RATING
200 m
single-gas to rebreather
SMARTWATCH
25 days
10 days always-on
MEMORY
32 GB
maps, music and dive logs
Sapphire crystal lens Titanium rear cover Leakproof metal buttons USB-C clip charger
Garmin Descent Mk3i 51mm, depth and NDL data on the dive screen

Planning a dive

How it works

Gas planning
A basic NDL and multi-gas deco planner runs on the watch, and PO2 goes up to 2.0 with a customizable deco setting for technical mixes.
Tank pressure
Each paired Descent T2 transceiver reports its tank over SubWave, so gas time remaining and your gas consumption rate sit on the wrist.

Between dives

Key features

Surface GPS
Entry and exit points for each dive
Surface diver status
A widget for the surface interval
Tides
Tide data through your paired smartphone
Boating profiles
Sailing and sail racing with an anchor alarm

Made for the 51 mm

How to use it

Garmin Descent Mk3i 51mm, the coated titanium bezel and buttons
Case

Carbon gray DLC bezel

The bezel is diamond-like carbon (DLC) coated titanium, and the fiber-reinforced polymer case closes with a titanium rear cover. The case is 16.4 mm thick under its sapphire lens.

  • QuickFit 26 mm band compatible
  • Silicone band fits 135-230 mm wrists
  • Extra-long silicone band fits 135-355 mm
Garmin Descent Mk3i 51mm, its wrist sensor for training data
Training

Training readiness on land

Training readiness, a daily score built from your sleep, recovery and recent training load, tells you how hard the next run or swim can be. Endurance score and hill score follow your fitness on land.

  • Garmin Coach plans
  • PacePro pacing for a set course
  • Animated cardio, strength, yoga and Pilates workouts
Garmin Descent Mk3i 51mm on the carbon gray DLC titanium band
Bracelet

The titanium band option

On its DLC titanium band, the whole watch weighs 165.9 g and fits wrists from 135 to 220 mm. That version also ships with a black QuickFit 26 silicone band, so you can switch between metal and silicone.

  • Black extra-long adjustment strap in the box
  • USB-C clip charging and data cable

Descent Mk3i at depth

Videos

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How it compares

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Garmin Descent Mk3i 51mm, dive computer in carbon gray
Garmin Descent Mk3i 51mm Dive Smartwatch
51 mm dive computer with an LED flashlight that works above or below water.
200 m dive rating Up to 66 hr dive mode 1.4 in. AMOLED
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Descent Mk3i 51 mm

Frequently asked questions

The silicone-band version comes with the watch on a black silicone band, a black extra-long adjustment strap, a USB-C clip charging and data cable, and documentation. The titanium-band version adds a black QuickFit 26 silicone band.
77.8 g with no band, 105.6 g on the silicone band and 165.9 g on the titanium band. The case measures 51 x 51 x 16.4 mm.
One Descent T2 transceiver per tank, sold separately, paired to the watch over SubWave. It reads up to 8 transceivers.
200 meters, with a sapphire lens over the 1.4-inch display. The diving features of this device are for use by certified divers only. This device should not be used as a sole dive computer.
Yes. Apnea, apnea hunt and pool apnea modes cover freediving, and the variometer gives descent and ascent feedback on each breath-hold.
Yes. DiveView maps show bathymetric contours and more than 4,000 dive sites.
Yes. Pair it with an inReach device (sold separately; active satellite subscription required) to trigger an SOS message while above the surface.
Garmin backs it with a one-year limited warranty from the date of purchase against defects in materials or workmanship, and Garmin repairs or replaces defective components.
  • Display type: AMOLED
  • Touchscreen: Yes
  • Display size: 1.4 in. (35.56 mm) diameter
  • Display resolution: 454 x 454 pixels
  • Color display: Yes
  • Large font option: Yes
  • Water rating: Dive (200 meters)
  • Lens material: Sapphire crystal
  • Bezel material: Diamond-like Carbon (DLC) coated titanium
  • Case material: Fiber-reinforced polymer with titanium rear cover
  • Strap material: Silicone or titanium
  • Leakproof inductive buttons: Yes
  • QuickFit watch band compatible: Yes (26 mm)
  • LED flashlight: Yes (works above or below water)
  • Physical size: 51 x 51 x 16.4 mm
  • Fits wrists: Silicone band: 135-230 mm; extra long silicone band: 135-355 mm; titanium bracelet: 135-220 mm
  • Weight: No bands: 77.8 g; silicone band: 105.6 g; titanium band: 165.9 g
  • Battery life: Smartwatch: up to 25 days (10 days always-on); battery saver watch mode: up to 31 days; GPS only: up to 76 hours (56 hours always-on); all satellite systems: up to 55 hours (43 hours always-on); all satellite systems + multi-band: up to 48 hours (38 hours always-on); all satellite systems + music: up to 17 hours; max battery GPS: up to 118 hours; expedition GPS: up to 24 days; dive mode: up to 66 hours; dive mode with air integration: up to 40 hours
  • Charging method: Garmin proprietary clip charger
  • Memory/history: 32 GB
  • Dive activity maximum operating depth: 200 meters
  • Dive modes: Single-gas, multi-gas, gauge, apnea, apnea hunt, pool apnea, closed circuit rebreather (CCR)
  • Decompression model: Buhlmann ZHL-16c with gradient factors
  • Gas mixes: Air, nitrox and trimix, up to 100% O2; 1 bottom gas and up to 11 deco and/or backup gases
  • PO2: Up to 2.0 with customizable deco PO2 setting
  • Air integration: Yes (via SubWave; Descent T2 transceivers sold separately), up to 8 transmitters
  • Dive planner: Basic NDL and multi-gas deco planner
  • Dive alerts: Audible and vibration alarms for ascent rate, PO2, CNS/OTU, NDL, deco, gas switching, tank pressure and gas consumption rate; up to 40 customizable alerts per dive mode, by depth or time
  • Backlight: Configurable time and intensity; auto-on at depth
  • Conservatism: Low, medium, high or custom using gradient factors
  • Missed deco lockout: Yes (can be disabled prior to dive with user acknowledgement)
  • Boating: Boating, sailing and sail racing profiles; anchor alarm; autopilot control; tack assist
  • Built-in mapping: Yes
  • Music storage: Yes
  • Garmin Pay: Yes
  • Multi-band GPS: Yes
  • Pulse Ox blood oxygen: Yes
  • Sleep score and insights: Yes
  • Training readiness: Yes
  • Training status: Yes (improved)
  • Wrist-based heart rate (constant, every second): Yes
  • Abnormal heart rate alerts: Yes (high and low)
  • Body Battery energy monitor: Yes
  • Skin temperature: Yes
  • Jet lag adviser: Yes
  • Health snapshot: Yes
  • Sensors: GPS, GLONASS, Galileo, SatIQ technology, Garmin Elevate wrist heart rate monitor, Pulse Ox, barometric altimeter, compass, gyroscope, accelerometer, thermometer, ambient light sensor, depth sensor
  • Connectivity: Bluetooth, ANT+, Wi-Fi, SubWave
  • Smartphone compatibility: iPhone, Android
  • Compatible with Garmin Messenger app: Yes
  • Red shift mode: Yes
  • Garmin Share: Yes
  • Stocks: Yes
  • Air integration with Descent T2 transceivers (sold separately)
  • SubWave sonar networking with diver-to-diver messaging and pressure monitoring (dive messaging is a supplemental feature and should not be relied upon as a method to receive emergency assistance)
  • Multiple dive modes including nitrox, trimix, gauge, apnea, and rebreather
  • Dive readiness tool based on sleep, exercise, stress, and jet lag
  • DiveView maps with bathymetric contours and 4,000+ dive sites
  • Bright 1.4-inch AMOLED display, sapphire lens, 200 m dive-rated case
  • Built-in LED flashlight that works above or below water
  • Dive log with sharing via Garmin Dive app
  • Up to 66 hours battery in dive mode; 25 days in smartwatch mode
  • Customizable dive modes with user-defined fields
  • Surface GPS to track dive entry and exit points
  • Garmin Dive app auto-syncs dive logs
  • Lume Mode for night vision with ambient light sensor
  • Underwater compass with built-in ABC sensors
  • GPS Reference Point for surface navigation to dive sites
  • Variometer for freedive descent/ascent feedback
  • Big Numbers Mode for simplified dive screen readability
  • Tide data via paired smartphone
  • inReach compatible for off-grid satellite messaging (inReach device sold separately; active satellite subscription required)
  • Preloaded sports apps: trail running, swimming, biking, rowing, golf, more
  • Surf activity tracking: wave count, speed, distance
  • Surfline camera + Sessions video and surf forecast widget (when paired with the Garmin Connect and Surfline apps)
  • Backcountry ski and snowboard metrics including cadence and stride
  • VO2 max for fitness level monitoring
  • Recovery time recommendations after training
  • Daily suggested workouts adapting to progress
  • Animated workouts for cardio, strength, yoga, Pilates
  • Wrist-based heart rate monitoring
  • Pulse Ox sensor for blood oxygen. This is not a medical device and is not intended for use in the diagnosis or monitoring of any medical condition.
  • Jet lag adviser with light/sleep/exercise guidance
  • Endurance score based on VO2 max and training load
  • Hill score for uphill strength and endurance
  • Garmin Coach with dynamic training plans
  • Sleep monitoring with stages, score, and insights
  • Women's health tracking for menstrual cycle or pregnancy. The menstrual cycle tracking feature should not be used in support of conception, contraception or birth control. This is not a medical device and is not intended for use in the diagnosis or monitoring of any medical condition.
  • SatIQ tech for optimized multi-band GPS accuracy
  • Multicontinent TopoActive maps preloaded
  • SkiView maps for 2,000+ ski resorts
  • ABC sensors: altimeter, barometer, compass
  • PacePro strategy planning for GPS-based race pacing
  • Turn-by-turn navigation with Garmin Connect or 3rd-party courses
  • Round-trip routing with TrendLine popularity data
  • Safety and tracking: sends location if incident occurs (when paired with your compatible smartphone; not available while in dive mode)
  • Music storage and playback from Spotify, Deezer, Amazon Music (subscription may be required)
  • Garmin Pay contactless payments
  • Smart notifications for calls, texts, and emails (when paired with your compatible smartphone)
  • Connect IQ store access for apps, watch faces, and more
  • Descent Mk3i - 51 mm watch on a black silicone band or a DLC titanium band
  • Black QuickFit 26 silicone band (titanium band version)
  • Black extra-long adjustment strap
  • USB-C clip charging/data cable
  • Documentation