Between the ROG Phone 9 and MIX Fold 4, the ROG Phone 9 comes out ahead in front camera and refresh rate, while the MIX Fold 4 wins on wireless charging and screen size. Overall, the ROG Phone 9 scores 75.1 and the MIX Fold 4 scores 71.4 on our Mars Score.
Which should you buy?
The ROG Phone 9 edges ahead on the Mars Score (75.1 vs 71.4), but the 3.7-point gap is small enough that the right pick comes down to which spec advantages matter to you.
Pick the ROG Phone 9 if you photograph or shoot video regularly and want the better imaging pipeline of the two. The biggest gaps in its favor are front camera, refresh rate, antutu, among others.
Pick the MIX Fold 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 wireless charging, screen size, pixel density, among others.
Both ship with comparable ram, main camera, 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 ASUS - ROG Phone 9 wins
- ▲Front camera — 60.00% more. 32 MP vs 20 MP.
- ▲Refresh rate — 54.17% more. 185 Hz vs 120 Hz.
- ▲AnTuTu — 26.47% more. 2580000 vs 2040000.
- ▲Battery capacity — 13.73% more. 5800 mAh vs 5100 mAh.
- ▲Has Headphone jack.
Why Xiaomi - MIX Fold 4 wins
- ▲Wireless charging — 233.33% more. 50 W vs 15 W.
- ▲Screen size — 17.70% more. 7.98 " vs 6.78 ".
- ▲Pixel density — 3.61% more. 402 ppi vs 388 ppi.
- ▲Wired charging — 3.08% more. 67 W vs 65 W.
- ▲Weight — 1.00 g less. 226 vs 227.
- ▲Water resistance: IPX8 (vs IP68).
- ▲Promised OS updates: 4 (vs 3).
Spec comparison
Design
| Spec | ASUS - ROG Phone 9 | Xiaomi - MIX Fold 4 |
|---|---|---|
| Weight | 227 g | 226 glead |
| Thickness | 8.9 mmlead | 9.47 mm |
| Water resistanceⓘ | IP68 | IPX8lead |
| Form factor | bar | foldable_booklead |
Display
| Spec | ASUS - ROG Phone 9 | Xiaomi - MIX Fold 4 |
|---|---|---|
| Screen sizeⓘ | 6.78 " | 7.98 "lead |
| Pixel densityⓘ | 388 ppi | 402 ppilead |
| Refresh rateⓘ | 185 Hzlead | 120 Hz |
| Peak brightnessⓘ | 2500 nits | 3000 nitslead |
Performance
Cameras
| Spec | ASUS - ROG Phone 9 | Xiaomi - MIX Fold 4 |
|---|---|---|
| Main cameraⓘ | 50 MP | 50 MP |
| Front camera | 32 MPlead | 20 MP |
| Optical image stabilizationⓘ | true | true |
Battery
| Spec | ASUS - ROG Phone 9 | Xiaomi - MIX Fold 4 |
|---|---|---|
| Battery capacity | 5800 mAhlead | 5100 mAh |
| Wired chargingⓘ | 65 W | 67 Wlead |
| Wireless chargingⓘ | 15 W | 50 Wlead |
Connectivity
| Spec | ASUS - ROG Phone 9 | Xiaomi - MIX Fold 4 |
|---|---|---|
| 5G supportⓘ | true | true |
| Headphone jack | truelead | false |
| microSD slot | false | false |
Operating System
| Spec | ASUS - ROG Phone 9 | Xiaomi - MIX Fold 4 |
|---|---|---|
| OS | Android | Android |
| Promised OS updates | 3 years | 4 yearslead |
Frequently asked
Which has better battery, ROG Phone 9 or MIX Fold 4?+
ROG Phone 9 has 13.7% more battery — 5800 mAh vs 5100 mAh.
Which is lighter, ROG Phone 9 or MIX Fold 4?+
MIX Fold 4 is 1g lighter — 227g vs 226g.
Is ROG Phone 9 waterproof?+
ROG Phone 9 has an IP68 rating.
Does MIX Fold 4 support 5G?+
Yes, MIX Fold 4 supports 5G.
Which has a better camera, ROG Phone 9 or MIX Fold 4?+
MIX Fold 4 has a 50 MP main camera vs 50 MP.
Spec-level deep dives
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