Between the Fenix 8 (47mm) and Venu 4, the Fenix 8 (47mm) comes out ahead in battery life and water resistance, while the Venu 4 wins on weight. Overall, the Fenix 8 (47mm) scores 64.3 and the Venu 4 scores 58.5 on our Mars Score.
Which should you buy?
The Fenix 8 (47mm) edges ahead on the Mars Score (64.3 vs 58.5), but the 5.8-point gap is small enough that the right pick comes down to which spec advantages matter to you.
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. The biggest gaps in its favor are battery life, water resistance.
Pick the Venu 4 if you carry the device everywhere and weight or thickness has been the deciding factor before. Its strongest claims are weight.
Both ship with comparable ecg, display size, cellular, so those specs don't separate the two — focus on the differences below.
Bottom line: the Fenix 8 (47mm) is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why Garmin - Fenix 8 (47mm) wins
- ▲Battery life — 45.45% more. 384 h vs 264 h.
- ▲Water resistance — 5.00 ATM more. 10 vs 5.
Why Garmin - Venu 4 wins
- ▲Weight — 28.00 g less. 45 vs 73.
Spec comparison
Design
| Spec | Garmin - Fenix 8 (47mm) | Garmin - Venu 4 |
|---|---|---|
| Case size | 47 mmlead | 45 mm |
| Weight | 73 g | 45 glead |
| Case material | fiber-reinforced polymer | aluminum |
| Water resistanceⓘ | 10 ATMlead | 5 ATM |
Display
| Spec | Garmin - Fenix 8 (47mm) | Garmin - Venu 4 |
|---|---|---|
| Display size | 1.4 " | 1.4 " |
| Always-on display | true | true |
| Peak brightnessⓘ | 1000 nits | 1000 nits |
Health & Fitness
| Spec | Garmin - Fenix 8 (47mm) | Garmin - Venu 4 |
|---|---|---|
| ECG | true | true |
| SpO2 | true | true |
| Temperature sensor | true | true |
| Sleep tracking | true | true |
| Blood pressure | false | false |
Battery & Connectivity
| Spec | Garmin - Fenix 8 (47mm) | Garmin - Venu 4 |
|---|---|---|
| Battery life | 384 hlead | 264 h |
| GPS | true | true |
| Cellular | false | false |
| NFC | true | true |
| OS | Garmin OS | Garmin OS |
Frequently asked
Which has longer battery life, Fenix 8 (47mm) or Venu 4?+
Fenix 8 (47mm) lasts 384h vs 264h.
Do Fenix 8 (47mm) or Venu 4 support ECG?+
Both support ECG.
Which has cellular, Fenix 8 (47mm) or Venu 4?+
Neither offers cellular.
Spec-level deep dives
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