Samsung Galaxy S21 Ultra vs Xiaomi 18 Fold
37.2Performance91.6
56.3Display67
72Camera71.9
46.4Battery76.6
78.7Features86.7
5 spec wins — Samsung Galaxy S21 Ultra12 spec wins — Xiaomi 18 Fold
InnoReviews verdict
Xiaomi 18 Fold wins this phone face-off, 79.3 to 53.9, pulling ahead mainly in performance (+54) and battery (+30). 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 Samsung Galaxy S21 Ultra
- 186% higher Optical zoom: 10 x vs 3.5 x
- 150% higher Front camera: 40 MP vs 16 MP
- 35% higher Pixel density: 515 ppi vs 382 ppi
- 17% lower thickness: 8.9 mm vs 10.7 mm
- Has eSIM — the other doesn't
Reasons to pick the Xiaomi 18 Fold
- Stronger performance score: 92 vs 37
- Stronger display score: 67 vs 56
- Stronger battery score: 77 vs 46
- Stronger features score: 87 vs 79
- 400% higher telephoto: 50 MP vs 10 MP
Display
| Spec | Samsung Galaxy S21 Ultra | Xiaomi 18 Fold |
|---|---|---|
| Screen size | 6.8 ″ | 7.58 ″+11% |
| Panel type | LTPO AMOLED | Foldable LTPO AMOLED |
| Resolution | 3200x1440 | 2364x1672 |
| Pixel density | 515 ppi+35% | 382 ppi |
| Refresh rate | 120 Hz | 120 Hz |
| Peak brightness | 1,500 nits | 4,000 nits+167% |
| Screen-to-body | — | 90.6 % |
Performance
| Spec | Samsung Galaxy S21 Ultra | Xiaomi 18 Fold |
|---|---|---|
| Chipset | Samsung Exynos 2100 | Xiaomi XRing O3 |
| AnTuTuDifferent AnTuTu versions — not compared | 783,817Bottom 22% | 4,811,636 |
| AnTuTu 11 (CPU) | 263,424Bottom 17% | — |
| AnTuTu 11 (GPU) | 126,989Bottom 33% | — |
| AnTuTu 11 (Memory) | 165,563Bottom 35% | — |
| AnTuTu 11 (UX) | 227,841Bottom 20% | — |
| Geekbench 6 (single) | 1,430Top 46% | 3,448+141%Top 7% |
| Geekbench 6 (multi) | 3,550Bottom 50% | 12,758+259%Top 1% |
| RAM (max) | 12 GB | 16 GB+33% |
| Storage options | 128GB / 256GB / 512GB | 256/512GB/1TB |
| Storage type | UFS 3.1 | UFS 4.1 |
Camera
| Spec | Samsung Galaxy S21 Ultra | Xiaomi 18 Fold |
|---|---|---|
| Main camera | 108 MP | 200 MP+85% |
| Main aperture | f/1.8 | f/1.7 |
| Ultra-wide | 12 MP | 50 MP+317% |
| Telephoto | 10 MP | 50 MP+400% |
| Optical zoom | 10 x+186% | 3.5 x |
| Max video | 8K@24fps | 8K@24fps |
| Front camera | 40 MP+150% | 16 MP |
| OIS | Yes | Yes |
Battery
| Spec | Samsung Galaxy S21 Ultra | Xiaomi 18 Fold |
|---|---|---|
| Capacity | 5,000 mAh | 6,000 mAh+20% |
| Wired charging | 25 W | 67 W+168% |
| Wireless charging | 15 W | 50 W+233% |
Design
| Spec | Samsung Galaxy S21 Ultra | Xiaomi 18 Fold |
|---|---|---|
| Weight | 228 g | 219 g+4% |
| Thickness | 8.9 mm+17% | 10.7 mm |
| IP rating | IP68 | IP58/IP59 |
| Frame material | Aluminum | Aluminum |
Connectivity
| Spec | Samsung Galaxy S21 Ultra | Xiaomi 18 Fold |
|---|---|---|
| 5G | Yes | Yes |
| Wi-Fi | Wi-Fi 6E | Wi-Fi 7 |
| Bluetooth | 5.2 | 6.0 |
| NFC | Yes | Yes |
| USB | USB-C 3.2 | USB-C 3.2 |
| eSIM | Yes | No |
Software
| Spec | Samsung Galaxy S21 Ultra | Xiaomi 18 Fold |
|---|---|---|
| OS at launch | Android 11 (One UI 3.1) | Android 17 (HyperOS 4) |
| OS update pledge | 4 years | — |
Audio
| Spec | Samsung Galaxy S21 Ultra | Xiaomi 18 Fold |
|---|---|---|
| Stereo speakers | Yes | Yes |
| 3.5mm jack | No | No |
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