Garmin
fēnix® 8 – 47 mm, AMOLED vs fēnix® 8 – 51 mm, AMOLED
Size, specs & wrist fit compared
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Which one fits you
On wrists narrower than about 54mm, the fēnix® 8 – 47 mm, AMOLED is the safer pick — it stays proportionate down to roughly 49mm, where the fēnix® 8 – 51 mm, AMOLED starts to hang over the edge. Above 54mm both sit cleanly, and the fēnix® 8 – 51 mm, AMOLED gives you more presence.
The fēnix® 8 – 51 mm, AMOLED wears larger than the fēnix® 8 – 47 mm, AMOLED (51mm vs 47mm case), giving it more wrist presence — and needing a wider wrist to sit cleanly.
The fēnix® 8 – 47 mm, AMOLED is the slimmer of the two (13.8mm vs 14.7mm), so it slides under a cuff more easily.
On the wrist the fēnix® 8 – 47 mm, AMOLED feels lighter (80g vs 102g, case only).
The fēnix® 8 – 47 mm, AMOLED is middle-of-the-pack for thickness among the 91 47mm watches in the database.
Among the 43 51mm watches we hold thickness for, the fēnix® 8 – 51 mm, AMOLED is thinner than 93%, so it wears flatter than its width suggests.
The fēnix® 8 – 51 mm, AMOLED is 4mm wider, 4mm longer, 0.9mm thicker and 22g heavier than the fēnix® 8 – 47 mm, AMOLED. Both are circular.
fēnix® 8 – 47 mm, AMOLED
fēnix® 8 – 51 mm, AMOLED
Case width
47mm
51mm+4mm
Lug-to-lug
47mm
51mm+4mm
Thickness
13.8mm
14.7mm+0.9mm
Weight
80g
102g+22g
Switch or add watches
Garmin
fēnix® 8 – 47 mm, AMOLED
Garmin
fēnix® 8 – 51 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 – 47 mm, AMOLED47mm · 13.8mm thick
- Garmin fēnix® 8 – 51 mm, AMOLED51mm · 14.7mm thick
3D preview
fēnix® 8 – 47 mm, AMOLED vs fēnix® 8 – 51 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 Expedition GPS mode, where the 51 mm, AMOLED lasts 1.8× as long as the 47 mm, AMOLED (31 days against 17 days).
47 mm, AMOLED51 mm, AMOLED
Battery Saver
23 days41 daysExpedition GPS
17 days31 daysSmartwatch
16 days29 daysMax Battery GPS
81 hours145 hoursGPS Only
47 hours84 hoursAll Satellite Systems
38 hours68 hoursAll Satellite Systems + Multi-band
35 hours62 hoursAll Satellite Systems + Music
10 hours18 hours
Specifications
The short version
7 key specs| Spec | Garminfēnix® 8 – 47 mm, AMOLED | Garminfēnix® 8 – 51 mm, AMOLED |
|---|---|---|
| Case Width | 47mm | 51mm |
| Thickness | 13.8mm | 14.7mm |
| Weight | 80g | 102g |
| Shape | Circular | Circular |
| Display type | AMOLED | AMOLED |
| Battery life | Smartwatch: Up to 16 days (7 days always-on) Battery Saver Watch Mode: Up to 23 days GPS Only: Up to 47 hours (37 hours always-on) All Satellite Systems: Up to 38 hours (30 hours always-on) All Satellite Systems + Multi-band: Up to 35 hours (28 hours always-on)* All Satellite Systems + Music: Up to 10 hours Max Battery GPS: Up to 81 hours Expedition GPS: Up to 17 days *Assuming typical use with SatIQ technology | 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 |
| Released | 2024 | 2024 |
Every specification
333 specs| Spec | Garmin fēnix® 8 – 47 mm, AMOLED | Garmin fēnix® 8 – 51 mm, AMOLED |
|---|---|---|
| Overview | ||
| Family | Garmin | Garmin |
| General | ||
| Battery life | Smartwatch: Up to 16 days (7 days always-on) Battery Saver Watch Mode: Up to 23 days GPS Only: Up to 47 hours (37 hours always-on) All Satellite Systems: Up to 38 hours (30 hours always-on) All Satellite Systems + Multi-band: Up to 35 hours (28 hours always-on)* All Satellite Systems + Music: Up to 10 hours Max Battery GPS: Up to 81 hours Expedition GPS: Up to 17 days *Assuming typical use with SatIQ technology | 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 |
| Battery type | Lithium ion | Lithium ion |
| Display Size | 1.4” (35.56 mm) diameter | 1.4” (35.56 mm) diameter |
| Case material | fiber-reinforced polymer with metal rear cover | fiber-reinforced polymer with metal rear cover |
| Color display | Yes | Yes |
| Lens Material | Corning® Gorilla® Glass or sapphire crystal | Corning® Gorilla® Glass or sapphire crystal |
| Bezel Material | stainless steel or titanium | stainless steel or titanium |
| Memory/History | 32 GB | 32 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 | 454 x 454 pixels |
| Built-in speaker/microphone | Yes | Yes |
| Leakproof inductive buttons | Yes | Yes |
| QuickFit® watch band compatible | included (22 mm) | included (26 mm) |
| Sensors | ||
| 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) | yes (to 40 m) |
| 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 | 010-02904-10 | 010-02905-10 |
| Product ID | 1228429 | 1228171 |
| Product Name | fēnix® 8 – 47 mm, AMOLED | fēnix® 8 – 51 mm, AMOLED |
| Release Date | 8/27/2024 | 8/27/2024 |
| Product Variation | Sapphire, Titanium with Spark Orange/Graphite Silicone Band | Sapphire, Titanium with Spark Orange/Graphite 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 1.6 with customizable Deco settings | up to 1.6 with customizable Deco settings |
| Tides | Yes | Yes |
| Backlight | yes (configurable intensity; always on) | yes (configurable intensity; always on) |
| Gas mixes | Air, Nitrox (21-40% Oxygen) | Air, Nitrox (21-40% Oxygen) |
| APNEA mode | Yes | Yes |
| Deep Stops | yes (using custom Gradient Factors) | yes (using custom Gradient Factors) |
| No fly time | Yes | Yes |
| Safety Stop | yes (customizable off/3min/5min) | yes (customizable off/3min/5min) |
| Dive planner | yes (Basic NDL & Gas Planner) | yes (Basic NDL & Gas Planner) |
| Nitrox support | Yes | Yes |
| Alerts & alarms | yes (vibration only) | yes (vibration only) |
| Single-gas mode | 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) |
| Custom end-dive timeout | yes (20 sec to 10 min) | yes (20 sec to 10 min) |
| Customizable conservatism | yes (Low/Medium/High) | yes (Low/Medium/High) |
| Surface diver status widget | yes (Surface Interval, no fly time, N2 loading, CNS, OTU, and Tissue Compartment status) | yes (Surface Interval, no fly time, N2 loading, CNS, OTU, and Tissue Compartment status) |
| Automatic altitude adjustment | Yes | Yes |
| Dive ascent/descent rate indicator | Yes | Yes |
| Dive activity maximum operating depth | 40 meters | 40 meters |
| Sync dive log to Garmin Dive™ Mobile app | Yes | Yes |
| Automatically saves dive entry and exit locations | Yes | Yes |
| Boating Features | ||
| Wearable trolling motor remote | Yes | Yes |
| 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 |
| Swing Tempo | 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 (GCT balance with accessory) | yes (GCT balance with accessory) |
| 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 | 10 ATM | 10 ATM |
| Garmin Pay™ | Yes | Yes |
| Music storage | Yes | Yes |
| Garmin ECG App | Yes | Yes |
| LED flashlight | Yes | Yes |
| Multi-band GPS | Yes | Yes |
| Training status | Yes | Yes |
| 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 16 days (7 days always-on) | Up to 29 days (13 days always-on) |
| Make calls and send texts via voice | Yes | Yes |
| Activity Profiles | ||
| 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, Depth App | Scuba Diving (single gas), Apnea Diving, Depth App |
| 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, Indoor Walking, Pilates, Yoga | Walking, Indoor Walking, Pilates, Yoga |
| 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, Water Skiing, Wakeboarding, Wakesurfing, Tubing, Snorkeling, Whitewater | Stand Up Paddleboarding, Rowing, Kayaking, Surfing, Kiteboarding, Windsurfing, Fishing, Boating, Sailing, Water Skiing, Wakeboarding, Wakesurfing, Tubing, Snorkeling, 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, XC Skate Skiing, Backcountry Skiing, Ice Skating, Snowshoeing | Skiing, Snowboarding, Backcountry Snowboarding, XC Classic Skiing, XC Skate 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, Rucking, Indoor Climbing, Bouldering, Climbing, 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 | 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 | ||
| 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 |
| 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 (Sapphire Editions only) | yes (Sapphire Editions only) |
| 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 |
| Passcode | Yes | Yes |
| Connectivity | Bluetooth®, ANT+®, Wi-Fi® | Bluetooth®, ANT+®, Wi-Fi® |
| Garmin Share | Yes | Yes |
| Find My Phone | Yes | Yes |
| Find My Watch | Yes | Yes |
| Voice command | 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 |
| Bluetooth phone calling and voice assistant support | 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 Coach - Strength | Yes | 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 | Yes |
| Daily Suggested Workout - Cycling (Pace and Heart Rate Based) | Yes | Yes |
| Daily Suggested Workout - Running (Pace and Heart Rate Based) | Yes | Yes |
| Health & Wellness Monitoring | ||
| 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 | Yes |
| Fitness age | Yes | Yes |
| Sleep coach | 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 | Yes |
| Respiration rate | Yes | Yes |
| Skin temperature | Yes | Yes |
| Resting heart rate | Yes | Yes |
| Breathing variations | 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 |
| 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 |
| Workout benefit | 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 |
| 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 | 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 fēnix® 8 – 47 mm, AMOLED
Sits best on wrists ~49–67mm wide (≈ 13.1–17.9cm circumference).
Garmin fēnix® 8 – 51 mm, AMOLED
Sits best on wrists ~54–73mm wide (≈ 14.4–19.5cm circumference).
Frequently Asked Questions
Is the Garmin fēnix® 8 – 47 mm, AMOLED bigger than the Garmin fēnix® 8 – 51 mm, AMOLED?
The Garmin fēnix® 8 – 51 mm, AMOLED is bigger — 51mm vs 47mm case width.
Which fits a smaller wrist better, the Garmin fēnix® 8 – 47 mm, AMOLED or the Garmin fēnix® 8 – 51 mm, AMOLED?
The Garmin fēnix® 8 – 47 mm, AMOLED suits wrists around 49–67mm wide, and the Garmin fēnix® 8 – 51 mm, AMOLED around 54–73mm. The one with the smaller lower bound is the safer pick for a small wrist.
Can I see the Garmin fēnix® 8 – 47 mm, AMOLED and Garmin fēnix® 8 – 51 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.