Garmin Descent G2 vs Fenix 8 51mm AMOLED
Size, specs & wrist fit compared
Which one fits you
Under 18 cm (7.1 in) round, the Fenix 8 51mm AMOLED's lugs overhang and the Descent G2's do not; the Descent G2 fills the wrist at 17–19 cm, the Fenix 8 51mm AMOLED at 19 cm and up.
What else differs
- Screen: the Fenix 8 51mm AMOLED has the larger screen, 1.4 in across against 1.2 in on the Descent G2.
- Battery: 29 days for the Fenix 8 51mm AMOLED against 10 days for the Descent G2 in everyday use; 3.5 days for the Fenix 8 51mm AMOLED against 20 hours for the Descent G2 with GPS on.
Among the 52 smartwatches 51mm across that we hold thickness for, the Fenix 8 51mm AMOLED is thinner than 98%, so it wears flatter than its width suggests.
The Fenix 8 51mm AMOLED is 5.5mm wider, 0.5mm thinner and 37g heavier than the Descent G2.
Descent G2
Fenix 8 51mm AMOLED
Case width
45.5mm
51mm+5.5mm
Thickness
15.2mm
14.7mm−0.5mm
Weight
65g
102g+37g
Descent G2 or Fenix 8 51mm AMOLED by wrist size
| Wrist round (mm left each side) | Descent G2≈52.5mm lug to lug, est. | Fenix 8 51mm AMOLED≈58.5mm lug to lug, est. |
|---|---|---|
| 14 cm / 5.5 in | Overhangs (3.7mm over) | Overhangs (6.7mm over) |
| 15 cm / 5.9 in | Overhangs (2.1mm over) | Overhangs (5.1mm over) |
| 16 cm / 6.3 in | Overhangs (0.4mm over) | Overhangs (3.4mm over) |
| 17 cm / 6.7 in | Bold (1.2mm) | Overhangs (1.8mm over) |
| 18 cm / 7.1 in | Sweet spot (2.8mm) | Overhangs (0.2mm over) |
| 19 cm / 7.5 in | Sweet spot (4.4mm) | Bold (1.4mm) |
| 20 cm / 7.9 in | Balanced (6mm) | Sweet spot (3mm) |
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Garmin
Descent G2
Garmin
Fenix 8 51mm AMOLED
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Battery life compared
Furthest apart in All systems mode, where the Fenix 8 51mm AMOLED lasts 4.5× as long as the Descent G2 (2.8 days against 15 hours).
Descent G2Fenix 8 51mm AMOLED
Battery saver
12 days41 daysExpedition
10 days31 daysSmartwatch
10 days29 daysMax battery GPS
44 hours145 hoursGPS only
20 hours84 hoursAll systems
15 hours68 hoursAll systems + multi-band
—62 hoursDive
27 hours—All systems with music
—18 hours
More comparisons
2D Dimension Schematics
- Garmin Descent G2 45.5mm × ≈52.5mm (est.) · 15.2mm thick
- Garmin Fenix 8 51mm AMOLED 51mm × ≈58.5mm (est.) · 14.7mm thick
3D preview
Descent G2 vs Fenix 8 51mm AMOLED on a wrist
Specifications
The short version
7 key specs| Spec | GarminDescent G2 | GarminFenix 8 51mm AMOLED |
|---|---|---|
| Case Width | 45.5mm | 51mm |
| Thickness | 15.2mm | 14.7mm |
| Weight | 65g | 102g |
| Shape | Circular | Circular |
| Display type | AMOLED | AMOLED |
| Battery life | Dive Mode: Up to 27 hours Smartwatch: Up to 10 days (4 days always-on) Battery Saver Watch Mode: Up to 12 days GPS Only: Up to 20 hours All Satellite Systems: Up to 15 hours Max Battery GPS: Up to 44 hours Expedition GPS: Up to 10 days | 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 | 2025 | 2024 |
Where the specifications differ
44 differences| Spec | Garmin Descent G2 | Garmin Fenix 8 51mm AMOLED |
|---|---|---|
| General | ||
| Battery life | Dive Mode: Up to 27 hours Smartwatch: Up to 10 days (4 days always-on) Battery Saver Watch Mode: Up to 12 days GPS Only: Up to 20 hours All Satellite Systems: Up to 15 hours Max Battery GPS: Up to 44 hours Expedition GPS: Up to 10 days | 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 |
| Display Size | 1.2" (30.4 mm) diameter | 1.4” (35.56 mm) diameter |
| Case material | fiber-reinforced ocean-bound plastic | fiber-reinforced polymer with metal rear cover |
| Lens Material | sapphire crystal | Corning® Gorilla® Glass or sapphire crystal |
| Bezel Material | fiber-reinforced ocean-bound plastic | stainless steel or titanium |
| Memory/History | 4 GB | 32 GB |
| Charging method | Garmin proprietary clip charger | Garmin proprietary plug charger |
| Display resolution | 390 x 390 pixels | 454 x 454 pixels |
| QuickFit® watch band compatible | yes (22 mm) | included (26 mm) |
| Sensors | ||
| Depth sensor | Yes | yes (to 40 m) |
| Product Info | ||
| Main SKU | 010-02986-00 | 010-02905-10 |
| Product ID | 1558977 | 1228171 |
| Product Name | Descent™ G2 | fēnix® 8 – 51 mm, AMOLED |
| Release Date | 2/14/2025 | 8/27/2024 |
| Product Variation | Black with Black Band | Sapphire, Titanium with Spark Orange/Graphite Silicone Band |
| Diving Features | ||
| PO2 | Up to 2.0 with customizable deco PO2 setting | up to 1.6 with customizable Deco settings |
| Backlight | yes (configurable time and intensity; auto-on at depth) | yes (configurable intensity; always on) |
| Gas mixes | Air, Nitrox and Trimix up to 100% O2; 1 bottom gas and up to 11 deco and/or backup gasses. | Air, Nitrox (21-40% Oxygen) |
| Deep Stops | yes (using custom gradient factors) | yes (using custom Gradient Factors) |
| Dive planner | yes (basic NDL + multi-gas deco planner) | yes (Basic NDL & Gas Planner) |
| Alerts & alarms | Audible and vibration alarms for ascent rate, PO2, CNS/OTU, NDL, deco, gas switching. Customizable (up to 40) audible and/or vibration per dive mode, based on depth or time | 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 | yes with adjustable heading, quick change to 90R, 90L, and Reciprocal. Indicates degrees and direction back to set heading. |
| Decompression model | Bühlmann ZHL-16c with gradient factors | Bühlmann ZHL-16c with Gradient Factors |
| Custom end-dive timeout | yes (20s to 10 m) | yes (20 sec to 10 min) |
| Customizable conservatism | yes (low/medium/high or custom using gradient factors) | yes (Low/Medium/High) |
| Surface diver status widget | yes (surface interval, N2/HE loading, CNS, OTU and tissue compartment status) | yes (Surface Interval, no fly time, N2 loading, CNS, OTU, and Tissue Compartment status) |
| Dive activity maximum operating depth | 100 meters | 40 meters |
| Golfing Features | ||
| Measures shot distance (calculates exact yardage for shots from anywhere on course) | manual | automatic |
| Running Features | ||
| Ground contact time and balance | Yes | yes (GCT balance with accessory) |
| What You'll Love | ||
| Water rating | Dive (100 meters) | 10 ATM |
| Pulse Ox blood oxygen | yes (spot-check, during sleep, all day) | Yes |
| Battery life (smartwatch mode) | up to 10 days (4 days always-on) | Up to 29 days (13 days always-on) |
| 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, Jump Roping |
| Dive | Diving | Scuba Diving (single gas), Apnea Diving, Depth App |
| Wellness | Walking, Pilates, Yoga , Indoor Walking | Walking, Indoor Walking, Pilates, Yoga |
| On the Water | Stand Up Paddleboarding, Rowing, Kayaking, Surfing, Kiteboarding, Windsurfing, Fishing, Boating, 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 |
| Snow & winter | Skiing, Snowboarding, Backcountry Snowboarding, XC Classic Skiing, Backcountry Skiing, Ice Skating, Snowshoeing | Skiing, Snowboarding, Backcountry Snowboarding, XC Classic Skiing, XC Skate Skiing, Backcountry Skiing, Ice Skating, Snowshoeing |
| Outdoor running | Running, Outdoor Track Running, Trail 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, Rucking, Indoor Climbing, Bouldering, Climbing, Hunting, Horseback Riding, Golfing, Disc Golf, Archery |
| Other activity profiles | Tactical, Inline Skating | Inline Skating |
| Daily Smart Features | ||
| Connectivity | Bluetooth® Smart, ANT+® | Bluetooth®, ANT+®, Wi-Fi® |
| Health & Wellness Monitoring | ||
| Sleep | Yes | yes (advanced) |
| Hydration | yes (in Garmin Connect™) | yes (in Garmin Connect™ and optional Connect IQ™ widget) |
| Women's health | yes (in Garmin Connect™) | yes (in Garmin Connect™ and optional Connect IQ™ widget) |
The other 224 specifications both list are identical.
Full Garmin Descent G2 specifications →Full Garmin Fenix 8 51mm AMOLED specifications →