Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Garmin - Fenix 8 (47mm) | Google - Pixel Watch 4 |
|---|---|---|
| Battery life | 384 h | 48 h |
| Peak brightness | 1000 nits | 3000 nits |
| Weight | 73 g | 37 g |
| Water resistance | 10 ATM | 5 ATM |
| Cellular | false | true |
Between the Fenix 8 (47mm) and Pixel Watch 4, the Fenix 8 (47mm) comes out ahead in battery life / water resistance, while the Pixel Watch 4 wins on peak brightness / weight. Overall, the Fenix 8 (47mm) scores 71.9 and the Pixel Watch 4 scores 69.8 on our Mars Score.
Which should you buy?
These two are nearly even on the Mars Score (71.9 vs 69.8). The decision is not about overall quality — both clear the bar — it is about which specific trade-offs fit your use.
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. The single most decisive one: Battery life — 700.00% more. 384 h vs 48 h.
Pick the Pixel Watch 4 if the display is what you stare at all day — refresh rate, brightness, or sharpness is where the difference will be most visible. Its strongest claims are peak brightness, weight, cellular. The single most decisive one: Peak brightness — 200.00% more. 3000 nits vs 1000 nits.
Both ship with comparable ecg, display size, spo2, so those specs do not 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 says both are well-rounded; the differences are about trade-offs, not quality.
Which should you buy: Garmin - Fenix 8 (47mm) or Google - Pixel Watch 4?
Garmin - Fenix 8 (47mm) leads the current Mars Score by 2.1 points.The more useful decision is the trade-off behind that result: compare battery life against the way you will actually use the product.
Choose Garmin - Fenix 8 (47mm) if…
Garmin - Fenix 8 (47mm) has the measurable edge on battery life h, water resistance atm.
Choose Google - Pixel Watch 4 if…
Google - Pixel Watch 4 has the measurable edge on peak brightness nits, weight g, has cellular.
This is a structured comparison of the published catalog values. It is not a claim of identical real-world performance across every workload; use the linked spec drill-downs and methodology page to inspect the inputs.
Why Garmin - Fenix 8 (47mm) wins
- ▲Battery life — 700.00% more. 384 h vs 48 h.
- ▲Water resistance — 5.00 ATM more. 10 vs 5.
Why Google - Pixel Watch 4 wins
- ▲Peak brightness — 200.00% more. 3000 nits vs 1000 nits.
- ▲Weight — 36.00 g less. 37 vs 73.
- ▲Has Cellular.
Spec comparison
Design
| Spec | Garmin - Fenix 8 (47mm) | Google - Pixel Watch 4 |
|---|---|---|
| Case size | 47 mmlead | 45 mm |
| Weight | 73 g | 37 glead |
| Case material | fiber-reinforced polymer | aluminum |
| Water resistanceⓘ | 10 ATMlead | 5 ATM |
Display
| Spec | Garmin - Fenix 8 (47mm) | Google - Pixel Watch 4 |
|---|---|---|
| Display size | 1.4 " | 1.4 " |
| Always-on display | true | true |
| Peak brightnessⓘ | 1000 nits | 3000 nitslead |
Health & Fitness
| Spec | Garmin - Fenix 8 (47mm) | Google - Pixel Watch 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) | Google - Pixel Watch 4 |
|---|---|---|
| Battery lifeⓘ | 384 hlead | 48 h |
| GPS | true | true |
| Cellular | false | truelead |
| NFC | true | true |
| OS | Garmin OSlead | WearOS |
Frequently asked
Which has longer battery life, Fenix 8 (47mm) or Pixel Watch 4?+
Fenix 8 (47mm) lasts 384 hours vs 48 hours.
Do Fenix 8 (47mm) or Pixel Watch 4 support ECG?+
Both support ECG.
Which has cellular, Fenix 8 (47mm) or Pixel Watch 4?+
Pixel Watch 4 offers a cellular variant; Fenix 8 (47mm) is Wi-Fi only.