Redmi K40S vs Samsung Galaxy S21 Ultra
53.5Performance37.2
48.8Display56.3
43.2Camera72
53.7Battery46.4
86.7Features78.7
8 spec wins — Redmi K40S8 spec wins — Samsung Galaxy S21 Ultra
InnoReviews verdict
This one is close to a dead heat: Redmi K40S scores 53.8 against 53.9 for Samsung Galaxy S21 Ultra. Pick by the categories that matter to you — Samsung Galaxy S21 Ultra edges ahead in camera and display, or by price.
Which would you pick?
Key differences
Reasons to pick the Redmi K40S
- Stronger performance score: 54 vs 37
- Stronger battery score: 54 vs 46
- Stronger features score: 87 vs 79
- 168% higher Wired charging: 67 W vs 25 W
- 44% higher AnTuTu 11 (CPU): 379,746 vs 263,424
Reasons to pick the Samsung Galaxy S21 Ultra
- Stronger display score: 56 vs 49
- Stronger camera score: 72 vs 43
- 125% higher Main camera: 108 MP vs 48 MP
- 100% higher Front camera: 40 MP vs 20 MP
- 50% higher ultra-wide: 12 MP vs 8 MP
Display
| Spec | Redmi K40S | Samsung Galaxy S21 Ultra |
|---|---|---|
| Screen size | 6.67 ″ | 6.8 ″+2% |
| Panel type | AMOLED | LTPO AMOLED |
| Resolution | 1080x2400 | 3200x1440 |
| Pixel density | 395 ppi | 515 ppi+30% |
| Refresh rate | 120 Hz | 120 Hz |
| Peak brightness | 1,300 nits | 1,500 nits+15% |
| Screen-to-body | 86.6 % | — |
Performance
| Spec | Redmi K40S | Samsung Galaxy S21 Ultra |
|---|---|---|
| Chipset | Snapdragon 870 | Samsung Exynos 2100 |
| AnTuTu 11 | 975,227+24%Bottom 23% | 783,817Bottom 11% |
| AnTuTu 11 (CPU) | 379,746+44%Bottom 30% | 263,424Bottom 11% |
| AnTuTu 11 (GPU) | 167,900+32%Bottom 24% | 126,989Bottom 18% |
| AnTuTu 11 (Memory) | 178,472+8%Bottom 29% | 165,563Bottom 22% |
| AnTuTu 11 (UX) | 249,109+9%Bottom 15% | 227,841Bottom 11% |
| Geekbench 6 (single) | — | 1,430Top 46% |
| Geekbench 6 (multi) | — | 3,550Bottom 50% |
| RAM (max) | 12 GB | 12 GB |
| Storage options | 128/256GB | 128GB / 256GB / 512GB |
| Storage type | UFS 3.1 | UFS 3.1 |
Camera
| Spec | Redmi K40S | Samsung Galaxy S21 Ultra |
|---|---|---|
| Main camera | 48 MP | 108 MP+125% |
| Main aperture | f/1.79 | f/1.8 |
| Ultra-wide | 8 MP | 12 MP+50% |
| Telephoto | — | 10 MP |
| Optical zoom | — | 10 x |
| Max video | 4K@30fps | 8K@24fps |
| Front camera | 20 MP | 40 MP+100% |
| OIS | Yes | Yes |
Battery
| Spec | Redmi K40S | Samsung Galaxy S21 Ultra |
|---|---|---|
| Capacity | 4,500 mAh | 5,000 mAh+11% |
| Wired charging | 67 W+168% | 25 W |
| Wireless charging | — | 15 W |
Design
| Spec | Redmi K40S | Samsung Galaxy S21 Ultra |
|---|---|---|
| Weight | 195 g+14% | 228 g |
| Thickness | 7.7 mm+13% | 8.9 mm |
| IP rating | — | IP68 |
| Frame material | — | Aluminum |
Connectivity
| Spec | Redmi K40S | Samsung Galaxy S21 Ultra |
|---|---|---|
| 5G | Yes | Yes |
| Wi-Fi | Wi-Fi 6 | Wi-Fi 6E |
| Bluetooth | 5.2 | 5.2 |
| NFC | Yes | Yes |
| USB | USB-C 2.0 | USB-C 3.2 |
| eSIM | No | Yes |
Software
| Spec | Redmi K40S | Samsung Galaxy S21 Ultra |
|---|---|---|
| OS at launch | Android 12 (MIUI 13) | Android 11 (One UI 3.1) |
| OS update pledge | — | 4 years |
Audio
| Spec | Redmi K40S | Samsung Galaxy S21 Ultra |
|---|---|---|
| Stereo speakers | Yes | Yes |
| 3.5mm jack | No | No |