Garmin
Descent™ Mk3i – 43 mm vs Descent™ Mk3i – 51 mm
Size, specs & wrist fit compared
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Which one fits you
On wrists narrower than about 54mm, the Descent™ Mk3i – 43 mm is the safer pick — it stays proportionate down to roughly 45mm, where the Descent™ Mk3i – 51 mm starts to hang over the edge. Above 54mm both sit cleanly, and the Descent™ Mk3i – 51 mm gives you more presence.
The Descent™ Mk3i – 51 mm wears larger than the Descent™ Mk3i – 43 mm (51mm vs 43mm case), giving it more wrist presence — and needing a wider wrist to sit cleanly.
The Descent™ Mk3i – 43 mm is the slimmer of the two (14.3mm vs 16.4mm), so it slides under a cuff more easily.
On the wrist the Descent™ Mk3i – 43 mm feels lighter (49.3g vs 77.8g, case only).
The Descent™ Mk3i – 43 mm is thicker than 74% of the 43mm watches we track and the Descent™ Mk3i – 51 mm than 78% of the 51mm ones — so both sit higher than their widths suggest.
The Descent™ Mk3i – 51 mm is 8mm wider, 8mm longer, 2.1mm thicker and 28.5g heavier than the Descent™ Mk3i – 43 mm. Both are circular.
Descent™ Mk3i – 43 mm
Descent™ Mk3i – 51 mm
Case width
43mm
51mm+8mm
Lug-to-lug
43mm
51mm+8mm
Thickness
14.3mm
16.4mm+2.1mm
Weight
49.3g
77.8g+28.5g
Switch or add watches
Garmin
Descent™ Mk3i – 43 mm
Garmin
Descent™ Mk3i – 51 mm
2D Dimension Schematics
Every case drawn to scale on a shared centre — from above, and in profile against the wrist.
Highlight
- Garmin Descent™ Mk3i – 43 mm43mm · 14.3mm thick
- Garmin Descent™ Mk3i – 51 mm51mm · 16.4mm thick
3D preview
Descent™ Mk3i – 43 mm vs Descent™ Mk3i – 51 mm on a wrist
Sized to your own wrist, turned any way you like.
Shapes are built from published measurements, not manufacturer 3D models — accurate proportions, generic dial.
Battery life compared
Furthest apart in All Satellite Systems + Music mode, where the 51 mm lasts 2.8× as long as the 43 mm (17 hours against 6 hours).
43 mm51 mm
Battery Saver
12 days31 daysSmartwatch
10 days25 daysExpedition GPS
10 days24 daysMax Battery GPS
44 hours118 hoursGPS Only
28 hours76 hoursDive
30 hours66 hoursAll Satellite Systems
20 hours55 hoursAll Satellite Systems + Multi-band
17 hours48 hoursDive with Air Integration
15 hours40 hoursAll Satellite Systems + Music
6 hours17 hours
Specifications
The short version
7 key specs| Spec | GarminDescent™ Mk3i – 43 mm | GarminDescent™ Mk3i – 51 mm |
|---|---|---|
| Case Width | 43mm | 51mm |
| Thickness | 14.3mm | 16.4mm |
| Weight | 49.3g | 77.8g |
| Shape | Circular | Circular |
| Display type | AMOLED | AMOLED |
| Battery life | Smartwatch: Up to 10 days (4 days always-on) Battery Saver Watch Mode: Up to 12 days GPS Only: Up to 28 hours (22 hours always-on ) All Satellite Systems: Up to 20 hours (16 hours always-on) All Satellite Systems + Multi-band: Up to 17 hours (14 hours always-on) All Satellite Systems + Music: Up to 6 hours Max Battery GPS: Up to 44 hours Expedition GPS: Up to 10 days Dive Mode: Up to 30 hours Dive Mode with Air Integration: Up to 15 hours | 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 |
| Released | 2023 | 2023 |
Every specification
348 specs| Spec | Garmin Descent™ Mk3i – 43 mm | Garmin Descent™ Mk3i – 51 mm |
|---|---|---|
| Overview | ||
| Family | Garmin | Garmin |
| General | ||
| Battery life | Smartwatch: Up to 10 days (4 days always-on) Battery Saver Watch Mode: Up to 12 days GPS Only: Up to 28 hours (22 hours always-on ) All Satellite Systems: Up to 20 hours (16 hours always-on) All Satellite Systems + Multi-band: Up to 17 hours (14 hours always-on) All Satellite Systems + Music: Up to 6 hours Max Battery GPS: Up to 44 hours Expedition GPS: Up to 10 days Dive Mode: Up to 30 hours Dive Mode with Air Integration: Up to 15 hours | 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 |
| Display Size | 1.2” (30.4 mm) diameter | 1.4” diameter (35.56 mm) |
| Case material | fiber-reinforced polymer with titanium rear cover | fiber-reinforced polymer with titanium rear cover |
| Color display | Yes | Yes |
| Lens Material | sapphire crystal | sapphire crystal |
| Bezel Material | Diamond-like Carbon (DLC) coated titanium or bronze PVD coated titanium | Diamond-like Carbon (DLC) coated titanium |
| Memory/History | 32 GB | 32 GB |
| Strap material | silicone | silicone or DLC coated titanium |
| Charging method | Garmin proprietary clip charger | Garmin proprietary clip charger |
| Large font option | Yes | Yes |
| Display resolution | 390 x 390 pixels | 454 x 454 pixels |
| Leakproof inductive buttons | Yes | Yes |
| QuickFit® watch band compatible | yes (20 mm) | yes (26 mm) |
| Sensors | ||
| GPS | Yes | Yes |
| Compass | Yes | Yes |
| GLONASS | Yes | Yes |
| Galileo | Yes | Yes |
| Gyroscope | Yes | Yes |
| Thermometer | Yes | Yes |
| Depth sensor | Yes | Yes |
| Accelerometer | Yes | Yes |
| SatIQ™ Technology | Yes | Yes |
| Ambient light sensor | Yes | Yes |
| Barometric altimeter | Yes | Yes |
| Pulse Ox Blood Oxygen Saturation Monitor | Yes | Yes |
| Garmin Elevate™ wrist heart rate monitor | Yes | Yes |
| Product Info | ||
| Main SKU | 010-02753-13 | 010-02752-10 |
| Product ID | 852217 | 852159 |
| Product Name | Descent™ Mk3i – 43 mm | Descent™ Mk3i – 51 mm |
| Release Date | 11/15/2023 | 11/15/2023 |
| Product Variation | Bronze PVD Titanium with French Gray Silicone Band | Carbon Gray DLC Titanium with Black Silicone Band |
| Clock Features | ||
| Timer | Yes | Yes |
| Stopwatch | Yes | Yes |
| Time/date | Yes | Yes |
| Alarm clock | Yes | Yes |
| GPS Time Sync | Yes | Yes |
| Sunrise/sunset times | Yes | Yes |
| Automatic daylight saving time | Yes | Yes |
| Diving Features | ||
| PO2 | Up to 2.0 with customizable deco PO2 setting | Up to 2.0 with customizable deco PO2 setting |
| Tides | Yes | Yes |
| Backlight | yes (configurable time and intensity; auto-on at depth) | yes (configurable time and intensity; auto-on at depth) |
| Gas mixes | Air, Nitrox and Trimix, up to 100% O2; 1 bottom gas and up to 11 deco and/or backup gasses. | Air, Nitrox and Trimix, up to 100% O2; 1 bottom gas and up to 11 deco and/or backup gasses. |
| APNEA mode | Yes | Yes |
| Deep Stops | yes (using custom gradient factors) | yes (using custom gradient factors) |
| Gauge mode | Yes | Yes |
| Pool APNEA | Yes | Yes |
| No fly time | Yes | Yes |
| Safety Stop | yes (customizable off/3min/5min) | yes (customizable off/3min/5min) |
| Dive planner | yes (basic NDL + multi-gas deco planner) | yes (basic NDL + multi-gas deco planner) |
| Multi-gas mode | Yes | Yes |
| Nitrox support | Yes | Yes |
| Trimix support | Yes | Yes |
| APNEA hunt mode | Yes | Yes |
| Air integration | yes (via Subwave™) | yes (via Subwave™) |
| Alerts & alarms | Audible and vibration alarms for ascent rate, PO2, CNS/OTU, NDL, deco, gas switching, tank pressure, gas consumption rate. Customizable (up to 40) audible and/or vibration per dive mode, based on depth or time | Audible and vibration alarms for ascent rate, PO2, CNS/OTU, NDL, deco, gas switching, tank pressure, gas consumption rate. Customizable (up to 40) audible and/or vibration per dive mode, based on depth or time |
| Single-gas mode | Yes | Yes |
| Gas time remaining | Yes | Yes |
| Subwave™ Support | Yes | Yes |
| 3-axis dive compass | yes (with adjustable heading, quick change to 90R, 90L and reciprocal). Indicates degrees and direction back to set heading | yes (with adjustable heading, quick change to 90R, 90L and reciprocal). Indicates degrees and direction back to set heading |
| Auto start/end dive | Yes | Yes |
| Decompression model | Bühlmann ZHL-16c with gradient factors | Bühlmann ZHL-16c with gradient factors |
| Missed Deco Lockout | yes (can be disabled prior to dive with user acknowledgement) | yes (can be disabled prior to dive with user acknowledgement) |
| Gas consumption rate | Yes | Yes |
| Custom end-dive timeout | yes (20s to 10 m) | yes (20s to 10 m) |
| Custom dive data screens | Yes | Yes |
| Customizable conservatism | yes (low/medium/high or custom using gradient factors) | yes (low/medium/high or custom using gradient factors) |
| Surface diver status widget | yes (surface interval, N2/HE loading, CNS, OTU and tissue compartment status) | yes (surface interval, N2/HE loading, CNS, OTU and tissue compartment status) |
| Automatic altitude adjustment | Yes | Yes |
| Residual Tissue Loading Reset | yes (on the surface with user acknowledgement) | yes (on the surface with user acknowledgement) |
| Closed Circuit Rebreather (CCR) | Yes | Yes |
| Number of transmitters supported | 8 | 8 |
| Dive ascent/descent rate indicator | Yes | Yes |
| Dive activity maximum operating depth | 200 meters | 200 meters |
| Sync dive log to Garmin Dive™ Mobile app | Yes | Yes |
| Automatically saves dive entry and exit locations | Yes | Yes |
| Gaming Features | ||
| Gaming Activity | Yes | Yes |
| GameOn™ app compatible | Yes | Yes |
| Boating Features | ||
| Anchor Alarm | Yes | Yes |
| Countdown timer | Yes | Yes |
| Tack assist mode | Yes | Yes |
| Autopilot Control | Yes | Yes |
| Boat Data Streaming | CIQ | CIQ |
| Virtual starting line | Yes | Yes |
| Available Boating Profiles | Boating, Sailing, Sail Racing | Boating, Sailing, Sail Racing |
| Wearable trolling motor remote | Yes | Yes |
| Built-in barometer and tide tables | yes (downloadable tides) | yes (downloadable tides) |
| Cycling Features | ||
| Courses | Yes | Yes |
| Power guide | Yes | Yes |
| MTB Grit & Flow | Yes | Yes |
| Race an activity | Yes | Yes |
| Power meter compatible | Yes | Yes |
| Advanced cycling dynamics | Yes | Yes |
| Power curve and % FTP workouts | Yes | Yes |
| Compatible with Varia™ lights | Yes | Yes |
| FTP (Functional Threshold Power) | yes (with compatible accessory) | yes (with compatible accessory) |
| Compatible with Varia headlight camera | Yes | Yes |
| Speed and cadence sensor support (w/sensor) | Yes | Yes |
| Cycle Map (routable cycling-specific street map) | Yes | Yes |
| Bike lap and lap maximum power (with power sensor) | Yes | Yes |
| Compatible with Varia™ radar (rear-facing radar) | Yes | Yes |
| Compatible with Vector™ and Rally™ (power meters) | Yes | Yes |
| Compatible with Varia Vision™ (head-mounted display) | Yes | Yes |
| Alerts (triggers alarm when you reach goals including time, distance, heart rate or calories) | Yes | Yes |
| Golfing Features | ||
| PinPointer | Yes | Yes |
| Custom targets | Yes | Yes |
| Tempo Training | Yes | Yes |
| Virtual caddie | Yes | Yes |
| Full vector map | Yes | Yes |
| Handicap scoring | Yes | Yes |
| Tournament legal | Yes | Yes |
| Digital scorecard | Yes | Yes |
| Garmin AutoShot™ | Yes | Yes |
| PlaysLike distance | Yes | Yes |
| Round timer/odometer | Yes | Yes |
| Auto CourseView updates | Yes | Yes |
| Yardage to layups/doglegs | Yes | Yes |
| Hazards and course targets | Yes | Yes |
| Pairs with Garmin Golf app | Yes | Yes |
| Green View with manual pin position | Yes | Yes |
| Preloaded with 43,000 courses worldwide | Yes | Yes |
| Green Contours (with Garmin Golf membership) | Yes | Yes |
| CT10 Automatic club tracking compatible (requires accessory) | Yes | Yes |
| Yardage to F/M/B (distance to front, middle and back of green) | Yes | Yes |
| Stat tracking (strokes, putts per round, greens and fairways hit) | Yes | Yes |
| Wind speed and direction (requires connection to Garmin Golf app) | Yes | Yes |
| Touch-targeting (touch target on display to see the distance to any point) | Yes | Yes |
| Measures shot distance (calculates exact yardage for shots from anywhere on course) | automatic | automatic |
| Running Features | ||
| Hill score | Yes | Yes |
| Run workouts | Yes | Yes |
| Running power | Yes | Yes |
| Race predictor | Yes | Yes |
| Foot pod capable | Yes | Yes |
| Running dynamics | Yes | Yes |
| Lactate threshold | yes (with compatible accessory) | yes (with compatible accessory) |
| Grade-adjusted pace | Yes | Yes |
| Trail run auto climb | Yes | Yes |
| Performance condition | Yes | Yes |
| Run/Walk/Stand detection | Yes | Yes |
| Stride length (real time) | Yes | Yes |
| PacePro™ Pacing Strategies | Yes | Yes |
| Vertical oscillation and ratio | Yes | Yes |
| Ground contact time and balance | Yes | Yes |
| GPS-based distance, time and pace | Yes | Yes |
| Course- and weather-specific race predictor | Yes | Yes |
| Cadence (provides real-time number of steps per minute) | Yes | Yes |
| What You'll Love | ||
| Touchscreen | Yes | Yes |
| Display type | AMOLED | AMOLED |
| Water rating | Dive (200 meters) | Dive (200 meters) |
| Garmin Pay™ | Yes | Yes |
| Music storage | Yes | Yes |
| Multi-band GPS | Yes | Yes |
| Training status | yes (improved) | yes (improved) |
| Built-in mapping | Yes | Yes |
| Training readiness | Yes | Yes |
| Pulse Ox blood oxygen | Yes | Yes |
| Sleep score and insights | Yes | Yes |
| Battery life (smartwatch mode) | Up to 10 days (4 days always-on) | Up to 25 days (10 days always-on) |
| LED flashlight | — | Yes |
| Activity Profiles | ||
| Gym | Strength, HIIT, Cardio, Elliptical Training, Stair Stepping, Floor Climbing, Indoor Rowing | Strength, HIIT, Cardio, Elliptical Training, Stair Stepping, Floor Climbing, Indoor Rowing |
| Swim | Pool Swimming, Open Water Swimming | Pool Swimming, Open Water Swimming |
| Cycling | Biking, Road Biking, Mountain Biking, Gravel Biking, Bike Commuting, Bike Touring, eBiking, eMountain Biking, Indoor Biking, Cyclocross, BMX | Biking, Road Biking, Mountain Biking, Gravel Biking, Bike Commuting, Bike Touring, eBiking, eMountain Biking, Indoor Biking, Cyclocross, BMX |
| Wellness | Walking, Pilates, Yoga, Indoor Walking | Walking, Pilates, Yoga, Indoor Walking |
| Multisport | Swimming/Running, Triathlon | Swimming/Running, Triathlon |
| In the ring | Boxing, Mixed Martial Arts | Boxing, Mixed Martial Arts |
| Team sports | Basketball, Volleyball, Field Hockey, Ice Hockey, Football/Soccer, American Football, Lacrosse, Rugby, Ultimate Disc, Cricket, Softball, Baseball | Basketball, Volleyball, Field Hockey, Ice Hockey, Football/Soccer, American Football, Lacrosse, Rugby, Ultimate Disc, Cricket, Softball, Baseball |
| Motor sports | Motorcycling, Overlanding, Motocrossing, ATVing, Snowmobiling | Motorcycling, Overlanding, Motocrossing, ATVing, Snowmobiling |
| On the Water | Stand Up Paddleboarding, Rowing, Kayaking, Surfing, Kiteboarding, Windsurfing, Fishing, Boating, Sailing, Sail Racing, Water Skiing, Wakeboarding, Wakesurfing, Tubing, Snorkeling, Sailing Expedition, Whitewater | Stand Up Paddleboarding, Rowing, Kayaking, Surfing, Kiteboarding, Windsurfing, Fishing, Boating, Sailing, Sail Racing, Water Skiing, Wakeboarding, Wakesurfing, Tubing, Snorkeling, Sailing Expedition, Whitewater |
| Racket sports | Tennis, Pickleball, Badminton, Squash, Table Tennis, Padel, Platform Tennis, Racquetball | Tennis, Pickleball, Badminton, Squash, Table Tennis, Padel, Platform Tennis, Racquetball |
| Snow & winter | Skiing, Snowboarding, Backcountry Snowboarding, XC Classic Skiing, Backcountry Skiing, Ice Skating, Snowshoeing | Skiing, Snowboarding, Backcountry Snowboarding, XC Classic Skiing, Backcountry Skiing, Ice Skating, Snowshoeing |
| Indoor running | Treadmill Running, Indoor Track Running, Virtual Running | Treadmill Running, Indoor Track Running, Virtual Running |
| Outdoor running | Running, Outdoor Track Running, Trail Running, Ultra Running, Obstacle Racing | Running, Outdoor Track Running, Trail Running, Ultra Running, Obstacle Racing |
| Outdoor recreation | Hiking, Indoor Climbing, Bouldering, Climbing, Hunting, Horseback Riding, Golfing, Disc Golf, Archery | Hiking, Indoor Climbing, Bouldering, Climbing, Hunting, Horseback Riding, Golfing, Disc Golf, Archery |
| Other activity profiles | Jumpmaster, Tactical, Inline Skating | Jumpmaster, Tactical, Inline Skating |
| Swimming Features | ||
| Pool swim workouts | Yes | Yes |
| Critical swim speed | Yes | Yes |
| Time and distance alerts | Yes | Yes |
| Auto rest (pool swim only) | Yes | Yes |
| Drill logging (pool swim only) | Yes | Yes |
| Pacing alerts (pool swim only) | Yes | Yes |
| Countdown start (pool swim only) | Yes | Yes |
| Underwater wrist-based heart rate | Yes | Yes |
| "Repeat on" rest timer (pool swim only) | Yes | Yes |
| Basic rest timer (up from 0) (pool swim only) | Yes | Yes |
| Stroke type detection (freestyle, backstroke, breaststroke, butterfly) (pool swim only) | Yes | Yes |
| Pool swim metrics (lengths, distance, pace, stroke count, swim efficiency (SWOLF), calories) | Yes | Yes |
| Open-water swim metrics (distance, pace, stroke count/rate, stroke distance, swim efficiency (SWOLF), calories) | Yes | Yes |
| Heart rate from external HRM (real-time during rests, interval and session stats during rests, and automatic heart rate download post-swim) | yes (with HRM-Tri, HRM-Swim, HRM-Pro or HRM-Pro Plus) | yes (with HRM-Tri, HRM-Swim, HRM-Pro or HRM-Pro Plus) |
| Tactical Features | ||
| Kill switch | Yes | Yes |
| Stealth Mode | Yes | Yes |
| Ballistics solver | yes (unlock required) | yes (unlock required) |
| Night vision mode | Yes | Yes |
| XERO™ Locations | Yes | Yes |
| Dual grid coordinates | Yes | Yes |
| Outdoor Recreation | ||
| Tides | Yes | Yes |
| Up Ahead | Yes | Yes |
| Auto rest | Yes | Yes |
| TracBack® | Yes | Yes |
| Sight 'N Go | Yes | Yes |
| Tide glance | Yes | Yes |
| Back to start | Yes | Yes |
| Fish forecast | Yes | Yes |
| Explore Nearby | Yes | Yes |
| UltraTrac mode | Yes | Yes |
| Vertical speed | Yes | Yes |
| GPS coordinates | Yes | Yes |
| Reference point | Yes | Yes |
| Area calculation | yes (via Connect IQ™) | yes (via Connect IQ™) |
| Elevation profile | Yes | Yes |
| Projected waypoint | Yes | Yes |
| Total ascent/descent | Yes | Yes |
| Future elevation plot | Yes | Yes |
| NextFork™ navigation | Yes | Yes |
| Distance to destination | Yes | Yes |
| Expedition GPS Activity | Yes | Yes |
| Sun and moon information | Yes | Yes |
| Point-to-point navigation | Yes | Yes |
| Preloaded ski resort maps | Yes | Yes |
| ClimbPro™ Ascent Planner | Yes | Yes |
| Rest Timer (Ultra Run only) | Yes | Yes |
| Preloaded road and trail maps | Yes | Yes |
| Bread crumb trail in real time | Yes | Yes |
| Downloadable cartography support | Yes | Yes |
| Barometric trend indicator with Storm Alert | Yes | Yes |
| Daily Smart Features | ||
| Stocks | Yes | Yes |
| Calendar | Yes | Yes |
| Connectivity | BLUETOOTH®, ANT+®, Wi-Fi®, Subwave™ | Bluetooth®, ANT+®, Wi-Fi®, Subwave™ |
| Garmin Share | Yes | Yes |
| Find My Phone | Yes | Yes |
| Find My Watch | Yes | Yes |
| VIRB® Remote | Yes | Yes |
| Morning report | Yes | Yes |
| Red shift mode | Yes | Yes |
| Weather forecasts | Yes | Yes |
| Smart Notifications | Yes | Yes |
| Smart trainer control | Yes | Yes |
| Smartphone compatibility | iPhone®, Android™ | iPhone®, Android™ |
| Controls smartphone music | Yes | Yes |
| On-device Connect IQ™ Store | Yes | Yes |
| Plays and controls watch music | Yes | Yes |
| Find My Phone during GPS activity | Yes | Yes |
| Pairs with Garmin Connect™ Mobile | Yes | Yes |
| Compatible with Garmin Messenger app | Yes | Yes |
| Battery saver (customizable low power watch) | Yes | Yes |
| Realtime settings sync with Garmin Connect™ mobile | Yes | Yes |
| View images from notifications on watch (Android™ only) | Yes | Yes |
| Text response/reject phone call with text (Android™ only) | Yes | Yes |
| Connect IQ™ (downloadable watch faces, data fields and apps) | Yes | Yes |
| Activity Tracking Features | ||
| TrueUp™ | Yes | Yes |
| Move IQ™ | Yes | Yes |
| Step counter | Yes | Yes |
| Floors climbed | Yes | Yes |
| Calories burned | Yes | Yes |
| Distance traveled | Yes | Yes |
| Intensity minutes | Yes | Yes |
| Automatic rep counting | Yes | Yes |
| Garmin Connect™ Challenges app | yes (optional Connect IQ app) | yes (optional Connect IQ app) |
| Move alerts (displays on device after a period of inactivity) | Yes | Yes |
| Auto goal (learns your activity level and assigns a daily step goal) | Yes | Yes |
| Workout and Training Plans | ||
| HIIT workouts | Yes | Yes |
| Yoga workouts | Yes | Yes |
| Cardio workouts | Yes | Yes |
| Pilates workouts | Yes | Yes |
| Strength workouts | Yes | Yes |
| Garmin Cycling Coach | Yes | Yes |
| Garmin Running Coach | Yes | Yes |
| Garmin Running Coach Experts | Yes | Yes |
| On-screen workout animations | Yes | Yes |
| On-screen workout muscle maps | Yes | Yes |
| Daily Suggested Workout - Cycling | Yes | Yes |
| Daily Suggested Workout - Running | Yes | Yes |
| Garmin Coach - Prebuilt Cycling Plans | Yes | Yes |
| Health & Wellness Monitoring | ||
| Sleep | yes (advanced) | yes (advanced) |
| Hydration | yes (in Garmin Connect™) | yes (in Garmin Connect™) |
| Breathwork | Yes | Yes |
| Fitness age | yes (in app) | yes (in app) |
| Nap detection | Yes | Yes |
| All-day stress | Yes | Yes |
| Women's health | yes (in Garmin Connect™) | yes (in Garmin Connect™) |
| Health snapshot | Yes | Yes |
| Jet lag adviser | Yes | Yes |
| Respiration rate | Yes | Yes |
| Skin temperature | Yes | Yes |
| Resting heart rate | Yes | Yes |
| Abnormal heart rate alerts | yes (high and low) | yes (high and low) |
| Relaxation breathing timer | Yes | Yes |
| Body Battery™ energy monitor | Yes | Yes |
| Wrist-based heart rate (constant, every second) | Yes | Yes |
| Safety and Tracking Features | ||
| Assistance | Yes | Yes |
| Live Event Sharing | Yes | Yes |
| Incident Detection during select activities | Yes | Yes |
| Incident detection alert on phone for wearables | Yes | Yes |
| Kid Activity Tracking Features | ||
| Toe-to-Toe™ Challenges app | yes (optional Connect IQ Toe-to-Toe™ Challenges app) | yes (optional Connect IQ Toe-to-Toe™ Challenges app) |
| Training, Planning and Analysis Features | ||
| % HRR | Yes | Yes |
| % HR max | Yes | Yes |
| HR zones | Yes | Yes |
| HR alerts | Yes | Yes |
| Shortcuts | Yes | Yes |
| HRV status | Yes | Yes |
| Load ratio | Yes | Yes |
| Manual lap | Yes | Yes |
| Rest timer | Yes | Yes |
| Auto max HR | Yes | Yes |
| Auto scroll | Yes | Yes |
| Finish time | Yes | Yes |
| HR calories | Yes | Yes |
| Voice alerts | Yes | Yes |
| Custom alerts | Yes | Yes |
| Physio TrueUp | Yes | Yes |
| Recovery time | Yes | Yes |
| Training load | Yes | Yes |
| VO2 Max (Run) | Yes | Yes |
| Course guidance | Yes | Yes |
| Endurance score | Yes | Yes |
| Training effect | Yes | Yes |
| Virtual Partner | Yes | Yes |
| Race an Activity | Yes | Yes |
| Realtime stamina | Yes | Yes |
| Advanced workouts | Yes | Yes |
| Interval training | Yes | Yes |
| Race glance/widget | Yes | Yes |
| Training load focus | Yes | Yes |
| VO2 Max (Trail Run) | Yes | Yes |
| Garmin Live Segments | Yes | Yes |
| Strava Live Segments | Yes | Yes |
| GPS speed and distance | Yes | Yes |
| Improved recovery time | Yes | Yes |
| Configurable lap alerts | Yes | Yes |
| Customizable data pages | Yes | Yes |
| Unified training status | Yes | Yes |
| Touch and/or button lock | Yes | Yes |
| Activity history on watch | Yes | Yes |
| Downloadable training plans | Yes | Yes |
| Training effect (anaerobic) | Yes | Yes |
| Manual multisport activities | Yes | Yes |
| HRM running pace and distance | Yes | Yes |
| Heat and altitude acclimation | Yes | Yes |
| Customizable activity profiles | Yes | Yes |
| Trendline™ Popularity Routing | Yes | Yes |
| Auto Pause® automatic timer halt | Yes | Yes |
| Respiration rate (during exercise) | yes (with compatible accessory) | yes (with compatible accessory) |
| Auto Lap® interval tracking feature | Yes | Yes |
| Primary benefit (Training Effect labels) | Yes | Yes |
| Round-trip course creator (running/cycling) | Yes | Yes |
| Power Modes - customizable in-activity battery settings | Yes | Yes |
| HR broadcast (broadcasts HR data over ANT+® to paired devices) | Yes | Yes |
| Improved interval (includes open repeats, intervals data page, rest screen and auto detection) | Yes | Yes |
| HRV stress test (measures your heart rate variability while standing still, for 3 minutes, to provide you with an estimated stress level; the scale of this is 1 to 100; low scores indicate lower stress levels) | yes (with compatible accessory) | yes (with compatible accessory) |
Wrist Fit
Garmin Descent™ Mk3i – 43 mm
Sits best on wrists ~45–61mm wide (≈ 12.0–16.3cm circumference).
Garmin Descent™ Mk3i – 51 mm
Sits best on wrists ~54–73mm wide (≈ 14.4–19.5cm circumference).
Frequently Asked Questions
Is the Garmin Descent™ Mk3i – 43 mm bigger than the Garmin Descent™ Mk3i – 51 mm?
The Garmin Descent™ Mk3i – 51 mm is bigger — 51mm vs 43mm case width.
Which fits a smaller wrist better, the Garmin Descent™ Mk3i – 43 mm or the Garmin Descent™ Mk3i – 51 mm?
The Garmin Descent™ Mk3i – 43 mm suits wrists around 45–61mm wide, and the Garmin Descent™ Mk3i – 51 mm around 54–73mm. The one with the smaller lower bound is the safer pick for a small wrist.
Can I see the Garmin Descent™ Mk3i – 43 mm and Garmin Descent™ Mk3i – 51 mm side by side at true scale?
Yes — the schematics and photos above show both watches at matched scale, and our fit tool overlays each on your wrist width.