Garmin
fēnix® 8 – 51 mm, AMOLED vs Instinct® 3 – 50 mm, AMOLED
Size, specs & wrist fit compared
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Which one fits you
Both need much the same wrist — roughly 53–73mm across the flat of the wrist. Neither will fit where the other won't, so decide on thickness, weight and features instead.
The fēnix® 8 – 51 mm, AMOLED wears larger than the Instinct® 3 – 50 mm, AMOLED (51mm vs 50mm case), giving it more wrist presence — and needing a wider wrist to sit cleanly.
On the wrist the Instinct® 3 – 50 mm, AMOLED feels lighter (59g vs 102g, case only).
Among the 54 51mm watches we hold thickness for, the fēnix® 8 – 51 mm, AMOLED is thinner than 94%, so it wears flatter than its width suggests.
The fēnix® 8 – 51 mm, AMOLED is 1mm wider, 1mm longer, 0.3mm thicker and 43g heavier than the Instinct® 3 – 50 mm, AMOLED. Both are circular.
fēnix® 8 – 51 mm, AMOLED
Instinct® 3 – 50 mm, AMOLED
Case width
51mm
50mm−1mm
Lug-to-lug
51mm
50mm−1mm
Thickness
14.7mm
14.4mm−0.3mm
Weight
102g
59g−43g
Switch or add watches
Garmin
fēnix® 8 – 51 mm, AMOLED
Garmin
Instinct® 3 – 50 mm, AMOLED
2D Dimension Schematics
Every case drawn to scale on a shared centre — from above, and in profile against the wrist.
Highlight
- Garmin fēnix® 8 – 51 mm, AMOLED51mm · 14.7mm thick
- Garmin Instinct® 3 – 50 mm, AMOLED50mm · 14.4mm thick
3D preview
fēnix® 8 – 51 mm, AMOLED vs Instinct® 3 – 50 mm, AMOLED 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 Smartwatch mode, where the fēnix® 8 – 51 mm, AMOLED lasts 1.2× as long as the Instinct® 3 – 50 mm, AMOLED (29 days against 24 days).
fēnix® 8 – 51 mm, AMOLEDInstinct® 3 – 50 mm, AMOLED
Smartwatch
29 days24 days
Specifications
The short version
7 key specs| Spec | Garminfēnix® 8 – 51 mm, AMOLED | GarminInstinct® 3 – 50 mm, AMOLED |
|---|---|---|
| Case Width | 51mm | 50mm |
| Thickness | 14.7mm | 14.4mm |
| Weight | 102g | 59g |
| Shape | Circular | Circular |
| Display type | AMOLED | AMOLED (always-on) |
| Battery life | Smartwatch: Up to 29 days (13 days always-on) Battery Saver Watch Mode: Up to 41 days GPS Only: Up to 84 hours (65 hours always-on) All Satellite Systems: Up to 68 hours (54 hours always-on) All Satellite Systems + Multi-band: Up to 62 hours (49 hours always-on)* All Satellite Systems + Music: Up to 18 hours Max Battery GPS: Up to 145 hours Expedition GPS: Up to 31 days *Assuming typical use with SatIQ technology | Smartwatch: Up to 24 days (9 days always-on) Battery Saver Watch Mode: Up to 30 days GPS Only: Up to 40 hours All Satellite Systems: Up to 32 hours All Satellite Systems + Multi-Band: Up to 30 hours* Max Battery GPS: Up to 86 hours Expedition GPS: Up to 20 days *assuming typical use with SatIQ technology |
| Released | 2024 | 2025 |
Every specification
375 specs| Spec | Garmin fēnix® 8 – 51 mm, AMOLED | Garmin Instinct® 3 – 50 mm, AMOLED |
|---|---|---|
| Overview | ||
| Family | Garmin | Garmin |
| General | ||
| Timer | Yes | Yes |
| Stopwatch | Yes | Yes |
| Time/date | Yes | Yes |
| Alarm clock | Yes | Yes |
| Touchscreen | Yes | — |
| Display type | AMOLED | AMOLED (always-on) |
| Water rating | 10 ATM | 10 ATM |
| GPS Time Sync | Yes | Yes |
| Garmin Pay™ | Yes | Yes |
| Music storage | Yes | — |
| Garmin ECG app | Yes | — |
| LED flashlight | Yes | Yes |
| Multi-band GPS | Yes | Yes |
| Training status | Yes | Yes |
| Built-in mapping | Yes | — |
| Smart wake alarm | Yes | — |
| Training readiness | Yes | Yes |
| Sunrise/sunset times | Yes | Yes |
| Pulse Ox blood oxygen | Yes | Yes |
| Sleep score and insights | Yes | Yes |
| Automatic daylight saving time | Yes | Yes |
| Battery life (smartwatch mode) | Up to 29 days (13 days always-on) | Up to 24 days (9 days always-on) |
| Make calls and send texts via voice | Yes | — |
| Sensors | ||
| Stocks | Yes | Yes |
| Calendar | Yes | Yes |
| Passcode | Yes | Yes |
| Calculator | Yes | — |
| Color shift | Yes | — |
| Connectivity | Bluetooth®, ANT+®, Wi-Fi® | Bluetooth®, ANT+® |
| Garmin Share | Yes | Yes |
| Find My Phone | Yes | Yes |
| Voice command | Yes | — |
| Evening report | 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 | — |
| Find My Phone during GPS activity | Yes | — |
| Pairs with Garmin Connect™ mobile | Yes | Yes |
| Compatible with Garmin Messenger app | Yes | Yes |
| Find My Garmin (helps locate lost device) | Yes | Yes |
| Battery saver (customizable low power watch) | Yes | Yes |
| Bluetooth phone calling and voice assistant support | 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 |
| Variant | ||
| Color | Slate Gray with Black Silicone Band | Fern Green with Fern Green Band |
| Version | fēnix 8 – AMOLED | Instinct 3 – AMOLED |
| Case Size | 51 mm | 50 mm |
| Solar Charging | No | No |
| Available Colors | Slate Gray with Black Silicone Band; Sapphire, Titanium with Spark Orange/Graphite Silicone Band; Sapphire, Carbon Gray DLC Titanium with Black/Pebble Gray Silicone Band | Fern Green with Fern Green Band; Black with Charcoal Band |
| Product Info | ||
| Price | 1099.99 USD | 399.99 USD |
| Sale Price | 849.99 USD | 349.99 USD |
| Clock Features | ||
| Sleep | yes (advanced) | yes (advanced) |
| Hydration | yes (in Garmin Connect™ and optional Connect IQ™ widget) | yes (in Garmin Connect™ and optional Connect IQ™ widget) |
| Breathwork | Yes | Yes |
| Meditation | Yes | — |
| Fitness age | Yes | Yes |
| Sleep coach | Yes | Yes |
| Health status | Yes | Yes |
| Nap detection | Yes | Yes |
| All-day stress | Yes | Yes |
| Women's health | yes (in Garmin Connect™ and optional Connect IQ™ widget) | yes (in Garmin Connect™ and optional Connect IQ™ widget) |
| Health snapshot | Yes | Yes |
| Jet lag adviser | Yes | — |
| Sleep alignment | Yes | — |
| Respiration rate | Yes | Yes |
| Skin temperature | Yes | — |
| Lifestyle logging | Yes | — |
| Resting heart rate | Yes | Yes |
| Breathing variations | Yes | Yes |
| Past ovulation estimates | Yes | — |
| Abnormal heart rate alerts | yes (high and low) | yes (high and low) |
| Relaxation breathing timer | Yes | Yes |
| Body Battery™ energy monitor | Yes | Yes |
| Heart rate (constant, every second) | Yes | Yes |
| Relaxation reminders | — | Yes |
| Diving Features | ||
| Wearable trolling motor remote | Yes | — |
| Boating Features | ||
| TrueUp™ | Yes | — |
| Move IQ™ | Yes | — |
| Step counter | Yes | — |
| Floors climbed | Yes | — |
| Calories burned | Yes | — |
| Distance traveled | Yes | — |
| Intensity minutes | Yes | — |
| Automatic rep counting | Yes | — |
| Garmin Connect™ Challenges app | yes (optional Connect IQ app) | — |
| Move alerts (displays on device after a period of inactivity) | Yes | — |
| Auto goal (learns your activity level and assigns a daily step goal) | Yes | — |
| Cycling Features | ||
| Pool swim workouts | Yes | Yes |
| Critical swim speed | 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 | — |
| 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 |
| Golfing Features | ||
| Tides | Yes | Yes |
| Auto rest | Yes | — |
| Sight 'N Go | Yes | Yes |
| Tide glance | Yes | Yes |
| Fish forecast | Yes | — |
| UltraTrac mode | Yes | Yes |
| Vertical speed | Yes | Yes |
| GPS coordinates | Yes | Yes |
| Elevation profile | Yes | Yes |
| Projected waypoint | Yes | Yes |
| Total ascent/descent | Yes | Yes |
| Future elevation plot | Yes | Yes |
| Distance to destination | Yes | Yes |
| Expedition GPS Activity | Yes | Yes |
| Sun and moon information | Yes | Yes |
| Rest timer (ultra run only) | Yes | — |
| Barometric trend indicator with storm alert | Yes | Yes |
| Area calculation | — | Yes |
| Running Features | ||
| PinPointer | Yes | — |
| Swing Tempo | Yes | — |
| Custom targets | Yes | — |
| Tempo Training | Yes | — |
| Virtual caddie | Yes | — |
| Full vector map | Yes | — |
| Handicap scoring | Yes | — |
| Tournament legal | Yes | Yes |
| Digital scorecard | Yes | Yes |
| Garmin AutoShot™ | Yes | Yes |
| PlaysLike distance | 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 | — |
| Green Contours (with Garmin Golf membership) | Yes | — |
| CT1 Automatic club tracking compatible (requires accessory) | 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 | — |
| Touch-targeting (touch target on display to see the distance to any point) | Yes | — |
| Measures shot distance (calculates exact yardage for shots from anywhere on course) | automatic | manual |
| What You'll Love | ||
| Weight | Stainless Steel: 102 g (case only: 74 g) Titanium: 92 g (case only: 64 g) | 59 g |
| Battery life | Smartwatch: Up to 29 days (13 days always-on) Battery Saver Watch Mode: Up to 41 days GPS Only: Up to 84 hours (65 hours always-on) All Satellite Systems: Up to 68 hours (54 hours always-on) All Satellite Systems + Multi-band: Up to 62 hours (49 hours always-on)* All Satellite Systems + Music: Up to 18 hours Max Battery GPS: Up to 145 hours Expedition GPS: Up to 31 days *Assuming typical use with SatIQ technology | Smartwatch: Up to 24 days (9 days always-on) Battery Saver Watch Mode: Up to 30 days GPS Only: Up to 40 hours All Satellite Systems: Up to 32 hours All Satellite Systems + Multi-Band: Up to 30 hours* Max Battery GPS: Up to 86 hours Expedition GPS: Up to 20 days *assuming typical use with SatIQ technology |
| Battery type | Lithium ion | Lithium ion |
| Display Size | 1.4” (35.56 mm) diameter | 1.3" (33 mm) diameter |
| Case material | fiber-reinforced polymer with metal rear cover | fiber-reinforced polymer |
| Color display | Yes | Yes |
| Lens material | Corning® Gorilla® Glass or sapphire crystal | Chemically Strengthened Glass |
| Physical size | 51 x 51 x 14.7 mm Fits wrists with the following circumference: Silicone band: 127-210 mm UltraFit Band: 127-225 mm Leather Band: 135-213 mm Metal Band: 135-225 mm | 50 x 50 x 14.4 mm Fits wrists with a circumference of 141-213 mm |
| Bezel material | stainless steel or titanium | fiber-reinforced polymer/aluminum |
| Memory/History | 32 GB | 4 GB |
| Strap material | silicone | silicone |
| Charging method | Garmin proprietary plug charger | Garmin proprietary plug charger |
| Large font option | Yes | Yes |
| Display resolution | 454 x 454 pixels | 416 x 416 pixels |
| Built-in speaker/microphone | Yes | — |
| Leakproof inductive buttons | Yes | — |
| QuickFit® watch band compatible | included (26 mm) | yes (26 mm) |
| Activity Profiles | ||
| Assistance | Yes | Yes |
| Live event sharing | Yes | Yes |
| Incident detection during select activities | Yes | Yes |
| Incident detection alert on phone for wearables | Yes | Yes |
| Tactical Features | ||
| PO2 | up to 1.6 with customizable Deco settings | — |
| Tides | Yes | — |
| Backlight | yes (configurable intensity; always on) | — |
| Gas mixes | Air, Nitrox (21-40% Oxygen) | — |
| APNEA mode | Yes | — |
| Deep stops | yes (using custom Gradient Factors) | — |
| No fly time | Yes | — |
| Safety stop | yes (customizable off/3min/5min) | — |
| Dive planner | yes (Basic NDL & Gas Planner) | — |
| Nitrox support | Yes | — |
| Single-gas mode | Yes | — |
| Alerts and alarms | yes (vibration only) | — |
| 3-axis dive compass | yes with adjustable heading, quick change to 90R, 90L, and Reciprocal. Indicates degrees and direction back to set heading. | — |
| Auto start/end dive | Yes | — |
| Decompression model | Bühlmann ZHL-16c with Gradient Factors | — |
| Missed deco lockout | yes (can be disabled prior to dive with user acknowledgement) | — |
| Custom end-dive timeout | yes (20 sec to 10 min) | — |
| Customizable conservatism | yes (Low/Medium/High) | — |
| Surface diver status widget | yes (Surface Interval, no fly time, N2 loading, CNS, OTU, and Tissue Compartment status) | — |
| Automatic altitude adjustment | Yes | — |
| Dive ascent/descent rate indicator | Yes | — |
| Dive activity maximum operating depth | 40 meters | — |
| Sync dive log to Garmin Dive™ Mobile app | Yes | — |
| Automatically saves dive entry and exit locations | Yes | — |
| Gaming Activity | — | Yes |
| GameOn™ app compatible | — | Yes |
| Outdoor Recreation | ||
| Up Ahead | Yes | — |
| TracBack® | Yes | Yes |
| Back to start | Yes | Yes |
| Explore Nearby | Yes | — |
| NextFork™ navigation | Yes | — |
| Point-to-point navigation | Yes | Yes |
| Preloaded ski resort maps | Yes | — |
| ClimbPro™ Ascent Planner | Yes | — |
| Preloaded road and trail maps | yes (Sapphire Editions only) | — |
| Bread crumb trail in real time | Yes | Yes |
| Downloadable cartography support | Yes | — |
| Reference point | — | Yes |
| Daily Smart Features | ||
| HIIT workouts | Yes | Yes |
| Yoga workouts | Yes | Yes |
| Cardio workouts | Yes | Yes |
| Pilates workouts | Yes | Yes |
| Strength workouts | Yes | Yes |
| Multisport workouts | Yes | — |
| Garmin cycling coach | Yes | — |
| Garmin running coach | Yes | — |
| Garmin triathlon coach | Yes | — |
| Garmin Coach - Strength | Yes | — |
| Garmin running coach experts | Yes | Yes |
| On-screen workout animations | Yes | Yes |
| On-screen workout muscle maps | Yes | Yes |
| Garmin Coach - Prebuilt cycling plans | Yes | — |
| Daily suggested workout - Cycling (pace and heart rate based) | Yes | Yes |
| Daily suggested workout - Running (pace and heart rate based) | Yes | Yes |
| Mapping & Navigation | ||
| Courses | Yes | Yes |
| Power guide | 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 | — |
| Compatible with Varia™ lights | Yes | Yes |
| FTP (Functional Threshold Power) | yes (with compatible accessory) | Yes |
| Compatible with Varia™ headlight camera | Yes | — |
| Speed and cadence sensor support (w/sensor) | Yes | Yes |
| Cycle Map (routable cycling-specific street map) | 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 |
| Alerts (triggers alarm when you reach goals including time, distance, heart rate or calories) | Yes | Yes |
| Compatible with Varia Vision™ (head-mounted display) | — | Yes |
| Activity Tracking 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 | — |
| Training effect | Yes | Yes |
| Virtual Partner | Yes | Yes |
| Workout benefit | Yes | Yes |
| Race an Activity | Yes | Yes |
| Realtime stamina | 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 | — |
| Strava Live Segments | Yes | — |
| GPS speed and distance | 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 |
| Multisport auto transition | 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 | — |
| 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 | — |
| 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) | — |
| Workout and Training Plans | ||
| Gym | Strength, HIIT, Cardio, Elliptical Training, Stair Stepping, Floor Climbing, Indoor Rowing, Jump Roping | Strength, HIIT, Cardio, Elliptical Training, Stair Stepping, Floor Climbing, Indoor Rowing, Jump Roping |
| Dive | Scuba Diving (single gas), Apnea Diving | — |
| 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, Mobility | Walking, Pilates, Yoga, Indoor Walking, Mobility |
| Multisport | Swimming/Running, Triathlon | Triathlon, Swimrunning |
| 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, Water Skiing, Wakeboarding, Wakesurfing, Tubing, Snorkeling, Whitewater | Stand Up Paddleboarding, Rowing, Kayaking, Surfing, Kiteboarding, Windsurfing, Fishing, Boating, Water Skiing, Snorkeling, Wakeboarding, Wakesurfing, Tubing, Whitewater |
| Racket sports | Tennis, Pickleball, Badminton, Squash, Table Tennis, Padel, Platform Tennis, Racquetball | Tennis, Pickleball, Badminton, Squash, Table Tennis, Padel, Platform Tennis, Racquetball |
| 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, Obstacle Racing |
| Snow and winter | Skiing, Snowboarding, Backcountry Snowboarding, XC Classic Skiing, XC Skate Skiing, Backcountry Skiing, Ice Skating, Snowshoeing | Skiing, Snowboarding, Backcountry Snowboarding, XC Classic Skiing, XC Skate Skiing, Backcountry Skiing, Ice Skating, Snowshoeing |
| Outdoor recreation | Hiking, Rucking, Indoor Climbing, Bouldering, Mountaineering, Hunting, Horseback Riding, Golfing, Disc Golf, Archery | Hiking, Rucking, Indoor Climbing, Bouldering, Climbing, Hunting, Horseback Riding, Golfing, Disc Golf, Archery |
| Other activity profiles | Inline Skating | Tactical, Inline Skating |
| Health & Wellness Monitoring | ||
| GPS | Yes | Yes |
| QZSS | Yes | Yes |
| BeiDou | Yes | Yes |
| Compass | Yes | Yes |
| GLONASS | Yes | Yes |
| Galileo | Yes | Yes |
| Gyroscope | Yes | Yes |
| Thermometer | Yes | Yes |
| Depth sensor | yes (to 40 m) | — |
| Accelerometer | Yes | Yes |
| SatIQ™ technology | Yes | Yes |
| Ambient light sensor | Yes | — |
| Barometric altimeter | Yes | Yes |
| Pulse Ox blood oxygen saturation monitor | Yes | Yes |
| Garmin Elevate™ wrist heart rate monitor | Yes | Yes |
| Safety and Tracking Features | ||
| Dual grid coordinates | Yes | Yes |
| XERO™ Locations | — | Yes |
| Training, Planning and Analysis Features | ||
| Hill score | Yes | — |
| Run workouts | Yes | Yes |
| Running power | Yes | Yes |
| Race predictor | Yes | Yes |
| Running economy | yes (with compatible accessory) | — |
| Step speed loss | yes (with compatible accessory) | — |
| Foot pod capable | Yes | Yes |
| Running dynamics | Yes | Yes |
| Lactate threshold | Yes | yes (with compatible accessory) |
| Running tolerance | Yes | — |
| 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 |
| Projected race time and pace | Yes | — |
| Vertical oscillation and ratio | Yes | Yes |
| Ground contact time and balance | yes (GCT balance with accessory) | yes (GCT balance with accessory) |
| GPS-based distance, time and pace | Yes | Yes |
| Course- and weather-specific race predictor | Yes | — |
| Cadence (provides real-time number of steps per minute) | Yes | Yes |
| Gaming Features | ||
| Workout tutorials | — | Yes |
| Easy break planning | — | Yes |
| Truck driver workouts | — | Yes |
| Truck plaza loyalty programs | — | Yes |
| Compatible with dēzl™ OTR truck navigators | — | Yes |
| Swimming Features | ||
| PrePass weigh station notifications and bypass decisions | — | Yes |
| Trucking Smartwatch Features | ||
| TrueUp™ | — | Yes |
| Move IQ™ | — | Yes |
| Step counter | — | Yes |
| Floors climbed | — | Yes |
| Calories burned | — | Yes |
| Distance traveled | — | Yes |
| Intensity minutes | — | Yes |
| Automatic rep counting | — | Yes |
| Garmin Connect™ Challenges app | — | yes (optional Connect IQ app) |
| Move alerts (displays on device after a period of inactivity) | — | Yes |
| Auto goal (learns your activity level and assigns a daily step goal) | — | Yes |
| Kid Activity Tracking Features | ||
| Toe-to-Toe™ Challenges app | — | yes (optional Connect IQ Toe-to-Toe™ Challenges app) |
Wrist Fit
Garmin fēnix® 8 – 51 mm, AMOLED
Sits best on wrists ~54–73mm wide (≈ 14.4–19.5cm circumference).
Garmin Instinct® 3 – 50 mm, AMOLED
Sits best on wrists ~53–71mm wide (≈ 14.2–19.0cm circumference).
Frequently Asked Questions
Is the Garmin fēnix® 8 – 51 mm, AMOLED bigger than the Garmin Instinct® 3 – 50 mm, AMOLED?
The Garmin fēnix® 8 – 51 mm, AMOLED is bigger — 51mm vs 50mm case width.
Which fits a smaller wrist better, the Garmin fēnix® 8 – 51 mm, AMOLED or the Garmin Instinct® 3 – 50 mm, AMOLED?
The Garmin fēnix® 8 – 51 mm, AMOLED suits wrists around 54–73mm wide, and the Garmin Instinct® 3 – 50 mm, AMOLED around 53–71mm. The one with the smaller lower bound is the safer pick for a small wrist.
Can I see the Garmin fēnix® 8 – 51 mm, AMOLED and Garmin Instinct® 3 – 50 mm, AMOLED 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.
Related Comparisons
Garmin fēnix® 8 – 51 mm, AMOLED vs Garmin fēnix® 8 – 51 mm, SolarGarmin Instinct® 3 – 50 mm, AMOLED vs Garmin Instinct 3 – 50 mm, Solar, Tactical EditionGarmin Instinct® 3 – 50 mm, AMOLED vs Garmin Instinct® 3 – 50 mm, AMOLED, Tactical EditionGarmin Instinct® 3 – 50 mm, AMOLED vs Garmin Instinct® 3 – 50 mm, SolarGarmin Instinct® 3 – 50 mm, AMOLED vs Garmin Instinct® 2X Solar - Tactical Edition