Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | Oura - Ring 4 | Xiaomi - Smart Band 10 |
|---|---|---|
| Battery life | 8 days | 21 days |
| Sport modes | 40 | 150 |
| Water resistance | 10 ATM | 5 ATM |
Between the Ring 4 and Smart Band 10, the Ring 4 comes out ahead in water resistance, while the Smart Band 10 wins on battery life / sport modes. Overall, the Ring 4 scores 63.8 and the Smart Band 10 scores 76.1 on our Mars Score.
Which should you buy?
The Smart Band 10 is the clear pick on raw spec strength, leading by 12.3 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
Pick the Ring 4 if you care most about water resistance. The biggest gaps in its favor are water resistance. The single most decisive one: Water resistance — 5.00 ATM more. 10 vs 5.
Pick the Smart Band 10 if you care most about battery life / sport modes. Its strongest claims are battery life, sport modes. The single most decisive one: Battery life — 162.50% more. 21 days vs 8 days.
Both ship with comparable gps, spo2, so those specs do not separate the two — focus on the differences below.
Bottom line: the Smart Band 10 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: Oura - Ring 4 or Xiaomi - Smart Band 10?
Xiaomi - Smart Band 10 leads the current Mars Score by 12.3 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 Oura - Ring 4 if…
Oura - Ring 4 has the measurable edge on water resistance atm.
Choose Xiaomi - Smart Band 10 if…
Xiaomi - Smart Band 10 has the measurable edge on battery days, sport modes.
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 Oura - Ring 4 wins
- ▲Water resistance — 5.00 ATM more. 10 vs 5.
Why Xiaomi - Smart Band 10 wins
- ▲Battery life — 162.50% more. 21 days vs 8 days.
- ▲Sport modes — 110.00 more. 150 vs 40.
Spec comparison
Fitness
| Spec | Oura - Ring 4 | Xiaomi - Smart Band 10 |
|---|---|---|
| GPS | false | false |
| Heart rate | true | true |
| SpO2 | true | true |
| Sleep tracking | true | true |
| Sport modes | 40 | 150lead |
Battery
| Spec | Oura - Ring 4 | Xiaomi - Smart Band 10 |
|---|---|---|
| Battery lifeⓘ | 8 days | 21 dayslead |
| Water resistanceⓘ | 10 ATMlead | 5 ATM |
Design
| Spec | Oura - Ring 4 | Xiaomi - Smart Band 10 |
|---|---|---|
| Display size | 0 " | 1.72 "lead |
| Weight | 3.3 glead | 16 g |