Realme C100x vs Redmi K90 Ultra
Comparing the Realme C100x (2026) and the Redmi K90 Ultra (2026) on specs and benchmarks. By overall MobileRank rating, the Redmi K90 Ultra leads — 61/100 vs 31/100 (a 30-point difference). Key differences: the Redmi K90 Ultra has the bigger battery (8550 mAh vs 7500).
Realme C100x
Redmi K90 Ultra
- Better design/ergonomics (50/100 vs 16/100)
- Bigger battery: 8550 vs 7500 mAh
- Higher refresh rate: 165Hz vs 120Hz
- Higher performance (65/100 vs 0/100)
- Better camera (32/100 vs 24/100)
- Longer battery life (77/100 vs 52/100)
- Better value for money (81/100 vs 55/100)
Comparing the Realme C100x vs the Redmi K90 Ultra, the Redmi K90 Ultra scores 30 points higher (61/100 vs 31/100). In the "performance" category, the Redmi K90 Ultra leads (65/100 vs 0/100). In the "battery" category, the Redmi K90 Ultra leads (77/100 vs 52/100). In the "value for money" category, the Redmi K90 Ultra leads (81/100 vs 55/100). In the "performance" category, the Redmi K90 Ultra significantly outperforms the Realme C100x (65/100 vs 0/100). In the "display" category, both devices are on the same level — 100/100. In the "camera" category, the Redmi K90 Ultra is a bit better (32/100 vs 24/100). In the "battery" category, the Redmi K90 Ultra notably outperforms the Realme C100x (77/100 vs 52/100). In the "design" category, the Realme C100x significantly outperforms the Redmi K90 Ultra (50/100 vs 16/100). In the "value for money" category, the Redmi K90 Ultra notably outperforms the Realme C100x (81/100 vs 55/100).
| Specification | Realme C100x | Redmi K90 Ultra | |
|---|---|---|---|
| Processor | — | Qualcomm Snapdragon 8 Elite | |
| AnTuTu | — | 2760000 | |
| Geekbench Single | — | 3050 | |
| Geekbench Multi | — | 9300 | |
| Display | 6.8" IPS LCD | 6.8" AMOLED | |
| Resolution | 720x1640 | 1280x2772 | |
| Refresh rate | 120 Hz | 165 Hz | |
| Battery | 7500 mAh | 8550 mAh | |
| Charging | — | 100W | |
| Main camera | 50 MP | 50 MP | |
| Ultrawide | 0 MP | 8 MP | |
| Front camera | 5 MP | 20 MP | |
| RAM | 4GB | 12GB / 16GB | |
| Storage | 128GB / 256GB | 256GB / 512GB | |
| OS | Android 16 | Android 16 | |
| Brightness (peak) | — | 3500 nits | |
| NFC | yes | yes | |
| Protection | IP64 | IP68/IP69 | |
| Dimensions | — | 162.9×77.9×8.2 mm | |
| Weight | — | 227 g | |
| Price | — | $420 |
Realme C100x
- Main: 50MP f/f/1.8
- Front: 5MP
Redmi K90 Ultra
- Main: 50MP f/1.7
- Ultrawide: 8MP
- Front: 20MP
Realme C100x
- 6.8" IPS LCD
- Resolution: 720x1640
- Refresh rate: 120 Hz
Redmi K90 Ultra
- 6.8" AMOLED
- Resolution: 1280x2772
- Refresh rate: 165 Hz
Realme C100x
- 7500 mAh
- No wireless charging
Redmi K90 Ultra
- 8550 mAh
- Wired: 100W
- No wireless charging
Realme C100x
Price unknownperformance
In the "performance" category, the Redmi K90 Ultra significantly outperforms the Realme C100x (65/100 vs 0/100).
display
In the "display" category, both devices are on the same level — 100/100.
camera
In the "camera" category, the Redmi K90 Ultra is a bit better (32/100 vs 24/100).
battery
In the "battery" category, the Redmi K90 Ultra notably outperforms the Realme C100x (77/100 vs 52/100).
design
In the "design" category, the Realme C100x significantly outperforms the Redmi K90 Ultra (50/100 vs 16/100).
value for money
In the "value for money" category, the Redmi K90 Ultra notably outperforms the Realme C100x (81/100 vs 55/100).
Which is better: the Realme C100x or the Redmi K90 Ultra?
The Redmi K90 Ultra significantly outperforms the Realme C100x by 30 points (61/100 vs 31/100).
What is the rating of the Realme C100x and the Redmi K90 Ultra?
The Realme C100x has a MobileRank rating of 31/100, the Redmi K90 Ultra — 61/100.
Which has the better camera: the Realme C100x or the Redmi K90 Ultra?
The Redmi K90 Ultra leads on camera score (32/100 vs 24/100).
Which is more powerful: the Realme C100x or the Redmi K90 Ultra?
The Redmi K90 Ultra leads on performance (65/100 vs 0/100).
Should you choose the Realme C100x over the Redmi K90 Ultra?
The Realme C100x is a better fit for everyday use. The Redmi K90 Ultra is a better fit for active users, those who care about battery life, budget-conscious buyers.