Apple - Watch Series 11 (45mm) vs Garmin - Fenix 8 (47mm)
Between the Watch Series 11 (45mm) and Fenix 8 (47mm), the Watch Series 11 (45mm) comes out ahead in peak brightness and display size, while the Fenix 8 (47mm) wins on battery life and water resistance. Overall, the Watch Series 11 (45mm) scores 60.5 and the Fenix 8 (47mm) scores 64.3 on our Mars Score.
Which should you buy?
The Fenix 8 (47mm) edges ahead on the Mars Score (60.5 vs 64.3), but the 3.8-point gap is small enough that the right pick comes down to which spec advantages matter to you.
Pick the Watch Series 11 (45mm) if the display is what you stare at all day — refresh rate, brightness, or sharpness is where the difference will be most visible. The biggest gaps in its favor are peak brightness, display size, weight, among others.
Pick the Fenix 8 (47mm) if your top frustration with your current device is running out of charge before the day ends — endurance is the lead spec here. Its strongest claims are battery life, water resistance.
Both ship with comparable ecg, spo2, so those specs don't separate the two — focus on the differences below.
Bottom line: there is no wrong answer here — match the spec advantages to how you actually use the product. The Mars Score parity tells you both are well-rounded; the differences are about trade-offs, not quality.
Why Apple - Watch Series 11 (45mm) wins
- ▲Peak brightness — 200.00% more. 3000 nits vs 1000 nits.
- ▲Display size — 37.14% more. 1.92 " vs 1.4 ".
- ▲Weight — 35.00 g less. 38 vs 73.
- ▲Has Cellular.
Why Garmin - Fenix 8 (47mm) wins
- ▲Battery life — 966.67% more. 384 h vs 36 h.
- ▲Water resistance — 5.00 ATM more. 10 vs 5.
Spec comparison
Design
| Spec | Apple - Watch Series 11 (45mm) | Garmin - Fenix 8 (47mm) |
|---|---|---|
| Case size | 45 mm | 47 mmlead |
| Weight | 38 glead | 73 g |
| Case material | aluminum | fiber-reinforced polymer |
| Water resistanceⓘ | 5 ATM | 10 ATMlead |
Display
| Spec | Apple - Watch Series 11 (45mm) | Garmin - Fenix 8 (47mm) |
|---|---|---|
| Display size | 1.92 "lead | 1.4 " |
| Always-on display | true | true |
| Peak brightnessⓘ | 3000 nitslead | 1000 nits |
Health & Fitness
| Spec | Apple - Watch Series 11 (45mm) | Garmin - Fenix 8 (47mm) |
|---|---|---|
| ECG | true | true |
| SpO2 | true | true |
| Temperature sensor | true | true |
| Sleep tracking | true | true |
| Blood pressure | false | false |
Battery & Connectivity
| Spec | Apple - Watch Series 11 (45mm) | Garmin - Fenix 8 (47mm) |
|---|---|---|
| Battery life | 36 h | 384 hlead |
| GPS | true | true |
| Cellular | truelead | false |
| NFC | true | true |
| OS | watchOS | Garmin OSlead |
Frequently asked
Which has longer battery life, Watch Series 11 (45mm) or Fenix 8 (47mm)?+
Fenix 8 (47mm) lasts 384h vs 36h.
Do Watch Series 11 (45mm) or Fenix 8 (47mm) support ECG?+
Both support ECG.
Which has cellular, Watch Series 11 (45mm) or Fenix 8 (47mm)?+
Watch Series 11 (45mm) offers a cellular variant; Fenix 8 (47mm) is Wi-Fi only.
Spec-level deep dives
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