Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Google - Pixel Watch 4 | Xiaomi - Watch S4 |
|---|---|---|
| Battery life | 48 h | 360 h |
| Peak brightness | 3000 nits | 2200 nits |
| Weight | 37 g | 44 g |
| Display size | 1.4 " | 1.43 " |
Between the Pixel Watch 4 and Watch S4, the Pixel Watch 4 comes out ahead in peak brightness / weight, while the Watch S4 wins on battery life / display size. Overall, the Pixel Watch 4 scores 69.8 and the Watch S4 scores 76.3 on our Mars Score.
Which should you buy?
The Watch S4 edges ahead on the Mars Score (69.8 vs 76.3), but the 6.5-point gap is small enough that the right pick comes down to which spec advantages matter to you.
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. The biggest gaps in its favor are peak brightness, weight. The single most decisive one: Peak brightness — 36.36% more. 3000 nits vs 2200 nits.
Pick the Watch S4 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, display size. The single most decisive one: Battery life — 650.00% more. 360 h vs 48 h.
Both ship with comparable ecg, cellular, spo2, so those specs do not separate the two — focus on the differences below.
Bottom line: the Watch S4 is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Which should you buy: Google - Pixel Watch 4 or Xiaomi - Watch S4?
Xiaomi - Watch S4 leads the current Mars Score by 6.5 points.The more useful decision is the trade-off behind that result: compare display size, battery life against the way you will actually use the product.
Choose Google - Pixel Watch 4 if…
Google - Pixel Watch 4 has the measurable edge on peak brightness nits, weight g.
Choose Xiaomi - Watch S4 if…
Xiaomi - Watch S4 has the measurable edge on battery life h, display size in.
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 Google - Pixel Watch 4 wins
- ▲Peak brightness — 36.36% more. 3000 nits vs 2200 nits.
- ▲Weight — 7.00 g less. 37 vs 44.
Why Xiaomi - Watch S4 wins
- ▲Battery life — 650.00% more. 360 h vs 48 h.
- ▲Display size — 2.14% more. 1.43 " vs 1.4 ".
Spec comparison
Design
| Spec | Google - Pixel Watch 4 | Xiaomi - Watch S4 |
|---|---|---|
| Case size | 45 mm | 47 mmlead |
| Weight | 37 glead | 44 g |
| Case material | aluminum | stainless steel |
| Water resistanceⓘ | 5 ATM | 5 ATM |
Display
| Spec | Google - Pixel Watch 4 | Xiaomi - Watch S4 |
|---|---|---|
| Display size | 1.4 " | 1.43 "lead |
| Always-on display | true | true |
| Peak brightnessⓘ | 3000 nitslead | 2200 nits |
Health & Fitness
| Spec | Google - Pixel Watch 4 | Xiaomi - Watch S4 |
|---|---|---|
| ECG | true | true |
| SpO2 | true | true |
| Temperature sensor | true | true |
| Sleep tracking | true | true |
| Blood pressure | false | false |
Battery & Connectivity
| Spec | Google - Pixel Watch 4 | Xiaomi - Watch S4 |
|---|---|---|
| Battery lifeⓘ | 48 h | 360 hlead |
| GPS | true | true |
| Cellular | true | true |
| NFC | true | true |
| OS | WearOS | HyperOSlead |
Frequently asked
Which has longer battery life, Pixel Watch 4 or Watch S4?+
Watch S4 lasts 360 hours vs 48 hours.
Do Pixel Watch 4 or Watch S4 support ECG?+
Both support ECG.
Which has cellular, Pixel Watch 4 or Watch S4?+
Both offer cellular variants.