Redmi K90 vs Samsung Galaxy S21 Ultra
84.3Performance37.2
65.4Display56.3
53.1Camera72
83.2Battery46.4
86.7Features78.7
12 spec wins — Redmi K907 spec wins — Samsung Galaxy S21 Ultra
InnoReviews verdict
Redmi K90 wins this phone face-off, 74.3 to 53.9, pulling ahead mainly in performance (+47) and battery (+37). Samsung Galaxy S21 Ultra still makes sense if its price or standout specs fit your needs better.
Which would you pick?
Key differences
Reasons to pick the Redmi K90
- Stronger performance score: 84 vs 37
- Stronger display score: 65 vs 56
- Stronger battery score: 83 vs 46
- Stronger features score: 87 vs 79
- 800% higher AnTuTu 11 (GPU): 1,143,259 vs 126,989
Reasons to pick the Samsung Galaxy S21 Ultra
- Stronger camera score: 72 vs 53
- 300% higher Optical zoom: 10 x vs 2.5 x
- 116% higher Main camera: 108 MP vs 50 MP
- 100% higher Front camera: 40 MP vs 20 MP
- 50% higher ultra-wide: 12 MP vs 8 MP
Display
| Spec | Redmi K90 | Samsung Galaxy S21 Ultra |
|---|---|---|
| Screen size | 6.59 ″ | 6.8 ″+3% |
| Panel type | AMOLED | LTPO AMOLED |
| Resolution | 2510x1156 | 3200x1440 |
| Pixel density | 419 ppi | 515 ppi+23% |
| Refresh rate | 120 Hz | 120 Hz |
| Peak brightness | 3,500 nits+133% | 1,500 nits |
| Screen-to-body | 89.8 % | — |
Performance
| Spec | Redmi K90 | Samsung Galaxy S21 Ultra |
|---|---|---|
| Chipset | Snapdragon 8 Elite | Samsung Exynos 2100 |
| AnTuTu 11 | 3,106,623+296%Top 11% | 783,817Bottom 22% |
| AnTuTu 11 (CPU) | 872,376+231%Top 15% | 263,424Bottom 17% |
| AnTuTu 11 (GPU) | 1,143,259+800%Top 13% | 126,989Bottom 33% |
| AnTuTu 11 (Memory) | 462,601+179%Top 6% | 165,563Bottom 35% |
| AnTuTu 11 (UX) | 628,387+176%Top 13% | 227,841Bottom 20% |
| Geekbench 6 (single) | — | 1,430Top 46% |
| Geekbench 6 (multi) | — | 3,550Bottom 50% |
| RAM (max) | 16 GB+33% | 12 GB |
| Storage options | 256GB / 512GB / 1TB | 128GB / 256GB / 512GB |
| Storage type | UFS | UFS 3.1 |
Camera
| Spec | Redmi K90 | Samsung Galaxy S21 Ultra |
|---|---|---|
| Main camera | 50 MP | 108 MP+116% |
| Main aperture | f/1.88 | f/1.8 |
| Ultra-wide | 8 MP | 12 MP+50% |
| Telephoto | 50 MP+400% | 10 MP |
| Optical zoom | 2.5 x | 10 x+300% |
| Max video | 8K@30fps | 8K@24fps |
| Front camera | 20 MP | 40 MP+100% |
| OIS | Yes | Yes |
Battery
| Spec | Redmi K90 | Samsung Galaxy S21 Ultra |
|---|---|---|
| Capacity | 7,100 mAh+42% | 5,000 mAh |
| Wired charging | 100 W+300% | 25 W |
| Wireless charging | — | 15 W |
Design
| Spec | Redmi K90 | Samsung Galaxy S21 Ultra |
|---|---|---|
| Weight | 206 g+10% | 228 g |
| Thickness | 8 mm+10% | 8.9 mm |
| IP rating | IP68 | IP68 |
| Frame material | Aluminum | Aluminum |
Connectivity
| Spec | Redmi K90 | Samsung Galaxy S21 Ultra |
|---|---|---|
| 5G | Yes | Yes |
| Wi-Fi | Wi-Fi 7 | Wi-Fi 6E |
| Bluetooth | 5.4 | 5.2 |
| NFC | Yes | Yes |
| USB | USB-C | USB-C 3.2 |
| eSIM | No | Yes |
Software
| Spec | Redmi K90 | Samsung Galaxy S21 Ultra |
|---|---|---|
| OS at launch | Android 16 (HyperOS 3) | Android 11 (One UI 3.1) |
| OS update pledge | — | 4 years |
Audio
| Spec | Redmi K90 | Samsung Galaxy S21 Ultra |
|---|---|---|
| Stereo speakers | Yes | Yes |
| 3.5mm jack | No | No |
Related comparisons
Redmi K90vs RedMagic 10 ProVSRedmi K90vs Xiaomi 15T ProVSRedmi K90vs Honor Magic8 Pro AirVSRedmi K90vs POCO F8 ProVSSamsung Galaxy S21 Ultravs realme P4 Power 5GVSSamsung Galaxy S21 Ultravs TECNO POVA Curve 2 5GVSSamsung Galaxy S21 Ultravs Motorola Edge 50 ProVSSamsung Galaxy S21 Ultravs iPhone 16eVS