Between the Galaxy S26 Ultra and Xiaomi 15 Ultra, the Galaxy S26 Ultra comes out ahead in main camera and screen size, while the Xiaomi 15 Ultra wins on wireless charging and front camera. Overall, the Galaxy S26 Ultra scores 75.6 and the Xiaomi 15 Ultra scores 73.8 on our Mars Score.
Which should you buy?
These two are nearly even on the Mars Score (75.6 vs 73.8). The decision isn't about overall quality — both clear the bar — it's about which specific trade-offs fit your use.
Pick the Galaxy S26 Ultra if you photograph or shoot video regularly and want the better imaging pipeline of the two. The biggest gaps in its favor are main camera, screen size, promised os updates.
Pick the Xiaomi 15 Ultra if you photograph or shoot video regularly and want the better imaging pipeline of the two. Its strongest claims are wireless charging, front camera, wired charging, among others.
Both ship with comparable ram, refresh rate, 5g support, 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 Samsung - Galaxy S26 Ultra wins
- ▲Main camera — 300.00% more. 200 MP vs 50 MP.
- ▲Screen size — 2.53% more. 6.9 " vs 6.73 ".
- ▲Promised OS updates: 7 (vs 4).
Why Xiaomi 15 Ultra wins
- ▲Wireless charging — 433.33% more. 80 W vs 15 W.
- ▲Front camera — 166.67% more. 32 MP vs 12 MP.
- ▲Wired charging — 38.46% more. 90 W vs 65 W.
- ▲Battery capacity — 20.00% more. 6000 mAh vs 5000 mAh.
- ▲AnTuTu — 17.75% more. 2720000 vs 2310000.
- ▲Pixel density — 4.19% more. 522 ppi vs 501 ppi.
- ▲Weight — 3.00 g less. 229 vs 232.
Spec comparison
Design
| Spec | Samsung - Galaxy S26 Ultra | Xiaomi 15 Ultra |
|---|---|---|
| Weight | 232 g | 229 glead |
| Thickness | 8.6 mmlead | 9.4 mm |
| Water resistanceⓘ | IP68 | IP68 |
| Form factor | bar | bar |
Display
| Spec | Samsung - Galaxy S26 Ultra | Xiaomi 15 Ultra |
|---|---|---|
| Screen sizeⓘ | 6.9 "lead | 6.73 " |
| Pixel densityⓘ | 501 ppi | 522 ppilead |
| Refresh rateⓘ | 120 Hz | 120 Hz |
| Peak brightnessⓘ | 2600 nits | 3200 nitslead |
Performance
Cameras
| Spec | Samsung - Galaxy S26 Ultra | Xiaomi 15 Ultra |
|---|---|---|
| Main cameraⓘ | 200 MPlead | 50 MP |
| Front camera | 12 MP | 32 MPlead |
| Optical image stabilizationⓘ | true | true |
Battery
| Spec | Samsung - Galaxy S26 Ultra | Xiaomi 15 Ultra |
|---|---|---|
| Battery capacity | 5000 mAh | 6000 mAhlead |
| Wired chargingⓘ | 65 W | 90 Wlead |
| Wireless chargingⓘ | 15 W | 80 Wlead |
Connectivity
| Spec | Samsung - Galaxy S26 Ultra | Xiaomi 15 Ultra |
|---|---|---|
| 5G supportⓘ | true | true |
| Headphone jack | false | false |
| microSD slot | false | false |
Operating System
| Spec | Samsung - Galaxy S26 Ultra | Xiaomi 15 Ultra |
|---|---|---|
| OS | Android | Android |
| Promised OS updates | 7 yearslead | 4 years |
Frequently asked
Which has better battery, Galaxy S26 Ultra or Xiaomi 15 Ultra?+
Xiaomi 15 Ultra has 20.0% more battery — 5000 mAh vs 6000 mAh.
Which is lighter, Galaxy S26 Ultra or Xiaomi 15 Ultra?+
Xiaomi 15 Ultra is 3g lighter — 232g vs 229g.
Is Galaxy S26 Ultra waterproof?+
Galaxy S26 Ultra has an IP68 rating.
Does Xiaomi 15 Ultra support 5G?+
Yes, Xiaomi 15 Ultra supports 5G.
Which has a better camera, Galaxy S26 Ultra or Xiaomi 15 Ultra?+
Galaxy S26 Ultra has a 200 MP main camera vs 50 MP.
Spec-level deep dives
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