Choosing between Garmin’s flagship running watch and its ultimate outdoor multisport platform is one of the toughest decisions facing serious athletes. The Forerunner 965 and Fenix 8 both offer stunning AMOLED displays, comprehensive training metrics, and multi-band GPS, but they’re built for very different users.
One prioritizes lightweight speed and efficiency. The other emphasizes extreme durability and adventure readiness. With a $400–600 price gap, understanding what you’re really paying for matters.
Quick Specifications Comparison
| Feature | Garmin Forerunner 965 | Garmin Fenix 8 |
|---|---|---|
| 💳 Pricing | 💲Check Price | 💲Check Price |
| Launch Date | March 2023 | August 2024 |
| Weight | 53g (without strap) | 60–80g (size dependent) |
| Case Size | 47mm (single size) | 43mm / 47mm / 51mm |
| Thickness | 13.2mm | 13.8–14.9mm |
| Display | 1.4″ AMOLED | 1.3–1.4″ AMOLED |
| Resolution | 454 × 454 | 416 × 416 to 454 × 454 |
| Lens | Gorilla Glass DX | Sapphire crystal |
| Bezel | Titanium | Titanium or stainless steel |
| Water Resistance | 5 ATM (50m) | 10 ATM (100m), dive-rated to 40m |
| Buttons | 5 mechanical + touchscreen | 5 inductive + touchscreen |
| Battery (Smartwatch) | 23 days / 7 days (AOD) | 29–48 days |
| Battery (Multi-band GPS) | 19 hours | 21–48 hours |
| Battery (GPS + Music) | 8.5 hours | 12 hours |
| Charging | ~1 hour (10–90%) | Slower (~2 hours) |
| GPS | Multi-band GNSS | Multi-band GNSS |
| HR Sensor | Elevate Gen 4 | Elevate Gen 5 |
| Speaker / Mic | Yes | Yes |
| LED Flashlight | No | Yes |
| Dive Computer | No | Yes (40m) |
| Solar Charging | No | Yes (select models) |
| Maps | Full-color topo | Topo + ski resort maps |
| Training Readiness | Yes | Yes |
| Advanced Stamina | Limited | Yes |
| Heat / Altitude Acclimation | No | Yes |
| Garmin Pay | Yes | Yes |
| Best For | Runners, triathletes | Adventurers, multi-sport athletes |
Quick Verdict
Choose the Garmin Forerunner 965 if you:
- Primarily run, cycle, or do triathlons
- Want the lightest possible watch at 53g
- Don’t need diving or extreme durability
- Want 95% of flagship features for far less money
- Prefer fast charging and all-day comfort
Choose the Garmin Fenix 8 if you:
- Need military-grade durability
- Want dive computer functionality
- Train in heat, altitude, or extreme conditions
- Want maximum battery life and solar charging
- Use an LED flashlight for night runs or hiking
Design and Build Quality
The Forerunner 965 is engineered for speed and comfort. Its polymer case and titanium bezel keep weight to just 53 grams, making it nearly unnoticeable during long runs, sleep tracking, or daily wear. The single 47mm size fits most wrists, though smaller wrists may find it large. The Gorilla Glass DX lens resists scratches well but isn’t as tough as sapphire.
The Fenix 8 is built like a tank. It offers three sizes, a sapphire crystal lens, reinforced casing, and inductive buttons that remain leakproof under water. With 10 ATM water resistance and dive certification to 40 meters, it’s suitable for scuba diving and extreme environments. It’s heavier, but still comfortable given its capabilities.
Display Technology
Both watches use vibrant AMOLED displays with excellent outdoor readability. The Forerunner 965’s 1.4-inch screen delivers crisp text and rich colors that are ideal for viewing training data mid-run. The Fenix 8 features Garmin’s brightest AMOLED yet, available in multiple sizes.
In real-world use, both displays perform equally well in direct sunlight, rain, and motion.
Battery Life
The Forerunner 965 delivers up to 23 days in smartwatch mode and 19 hours of multi-band GPS. That’s enough for most runners and triathletes, with fast charging adding convenience.
The Fenix 8 stretches battery life significantly, reaching up to 48 days in smartwatch mode and as much as 48 hours of GPS on larger solar models. This makes it ideal for ultra-distance races and multi-day expeditions without charging access.
GPS and Heart Rate Accuracy
Both watches use multi-band GNSS and deliver elite-level GPS accuracy. Testing shows near-identical track precision across marathons and trail runs.
The Fenix 8’s newer Elevate Gen 5 heart-rate sensor performs slightly better during high-intensity intervals and strength training, though both watches track steady-state running heart rate very well. For race-day precision, chest straps remain superior.
Training Features
Both watches include Garmin’s full training ecosystem: Training Readiness, HRV status, VO₂ max, race predictions, and Body Battery.
The Fenix 8 adds exclusive features such as heat and altitude acclimation tracking, endurance score, advanced real-time stamina, and more sport-specific profiles like diving and skiing.
For pure running and triathlon training, the Forerunner 965 already offers everything most athletes need.
Navigation and Mapping
Both watches include full-color maps and turn-by-turn navigation. The Fenix 8 adds ski resort maps with trail difficulty ratings, making it a better choice for winter sports and backcountry exploration.
For road runners and trail runners alike, navigation performance is excellent on both.
Smart Features
Both support phone calls, voice assistants, Garmin Pay, music storage, and smartphone notifications.
The Fenix 8 stands out with its built-in LED flashlight, offering adjustable brightness, red light mode, and strobe for emergencies—extremely useful for night training and outdoor safety.
Value Proposition
The Forerunner 965 delivers exceptional value, offering nearly all of Garmin’s advanced training features at roughly half the price of the Fenix 8.
The Fenix 8 justifies its premium only if you’ll actually use its exclusive capabilities—diving, extreme durability, solar charging, or extended battery life.
Final Recommendation
The Garmin Forerunner 965 is the best choice for most athletes. It’s light, fast-charging, packed with training metrics, and perfect for runners and triathletes who want top-tier performance without overpaying.
The Garmin Fenix 8 is ideal for adventurers and multi-sport athletes who need maximum durability, dive support, and ultra-long battery life. If your training goes far beyond the road, the premium makes sense.
Both are outstanding watches. The right choice depends on whether you want a focused running tool or an all-terrain adventure platform.