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Samsung Galaxy S21 Ultra 5G
Samsung Samsung Galaxy S21 Ultra 5G
2.7
Price TBA
View Details
★ Our Pick
Xiaomi 15 Ultra
Xiaomi Xiaomi 15 Ultra
512GB · 16GB RAM
4.3
From $1,099
View Details

Our Verdict

Analysis

Samsung Galaxy S21 Ultra 5G has the bigger display.

Overall Winner
Samsung Galaxy S21 Ultra 5G
Display Winner
Samsung Galaxy S21 Ultra 5G
Performance Winner
Tie
Camera Winner
Tie
Battery Winner
Tie
Value Winner
Tie

Specifications Comparison

Feature Samsung Galaxy S21 Ultra 5G Xiaomi 15 Ultra
Display size (in) 6.80 6.73
Charging (W) 25 90
Main camera (MP) 108.00 50.00
Selfie (MP) 40.00 32.00
Weight (g) 227 226
Thickness (mm) 8.90 9.35
Chipset Exynos 2100 (5 nm) - InternationalQualcomm SM8350 Snapdragon 888 5G (5 nm) - USA/China Snapdragon 8 Elite
OS Android 11, up to 4 major Android upgrades, One UI 7 Android 15, HyperOS 2

Pros & Cons

Samsung Galaxy S21 Ultra 5G

Xiaomi 15 Ultra

  • Outstanding camera versatility
  • Fast wired and wireless charging
  • Bright display
  • Heavy
  • Software still polishing animations
  • Limited availability in some regions

Every Spec, Side by Side

Specification
Samsung
Samsung Galaxy S21 Ultra 5G
Xiaomi
Xiaomi 15 Ultra
Battery 3 specs
Type
Li-Ion 5000 mAh
Market-dependent versions:· Si/C Li-Ion 5410 mAh - Global· Si/C Li-Ion 6000 mAh - China
Charging
25W wired, PD3.0 15W wireless (Qi) 4.5W reverse wireless
90W wired, 80W wireless
Capacity
5410 mAh
Body 5 specs
Dimensions
165.1 x 75.6 x 8.9 mm (6.5 x 2.98 x 0.35 in)
161.3 x 75.3 x 9.35 mm
Weight
227 g (Sub6), 229 g (mmWave) (8.01 oz)
226 g
Build
Glass front (Gorilla Glass Victus), glass back (Gorilla Glass Victus), aluminum frame
Glass front, glass-fiber reinforced plastic back or silicone polymer back (eco leather), aluminum frame
SIM
· Nano-SIM + eSIM· Nano-SIM + Nano-SIM + eSIM (max 2 at a time)
· Nano-SIM + Nano-SIM· Nano-SIM + Nano-SIM + eSIM + eSIM (max 2 at a time)
 
IP68 dust tight and water resistant (immersible up to 1.5m for 30 min) Stylus support
IP68 dust tight and water resistant (immersible up to 1.5m for 30 min) Aerospace-grade glass fiber
Connectivity 8 specs
WLAN
Wi-Fi 802.11 a/b/g/n/ac/6e, dual-band, Wi-Fi Direct
Wi-Fi 802.11 a/b/g/n/ac/6e/7, dual-band or tri-band, Wi-Fi Direct
Bluetooth
5.2, A2DP, LE
6.0, A2DP, LE, aptX HD, aptX Adaptive, LHDC 5
Positioning
GPS, GLONASS, BDS, GALILEO
GPS (L1+L5), BDS (B1I+B1c+B2a), GALILEO (E1+E5a), QZSS (L1+L5), NavIC (L5), GLONASS
NFC
Yes
Yes
Radio
FM radio (Snapdragon model only; market/operator dependent)
No
USB
USB Type-C 3.2, OTG
USB Type-C 3.2 Gen 2, DisplayPort, OTG
Infrared port
Yes
5G
Yes
Display 4 specs
Type
Dynamic AMOLED 2X, 120Hz, HDR10+, 1500 nits (peak)
LTPO AMOLED
Size
6.8 inches, 112.1 cm2 (~89.8% screen-to-body ratio)
6.73 inches
Resolution
1440 x 3200 pixels, 20:9 ratio (~515 ppi density)
1440 x 3200 pixels
Protection
Corning Gorilla Glass Victus
Xiaomi Shield Glass 2.0, Mohs level 6
Features 2 specs
Sensors
Fingerprint (under display, ultrasonic), accelerometer, gyro, proximity, compass, barometer
Fingerprint (under display, ultrasonic), accelerometer, proximity, gyro, compass, barometer
 
Samsung DeX, Samsung Wireless DeX (desktop experience support) Ultra Wideband (UWB) support
Two-way satellite communication (China model only)
Launch 2 specs
Announced
2021, January 14
2025, February 27
Status
Available. Released 2021, January 29
Available. Released 2025, February 27
Main Camera 3 specs
Quad
108 MP, f/1.8, 24mm (wide), 1/1.33", 0.8µm, PDAF, OIS 10 MP, f/2.4, 72mm (telephoto), 1/3.24", 1.22µm, dual pixel PDAF, OIS, 3x optical zoom 10 MP, f/4.9, 240mm (periscope telephoto), 1/3.24", 1.22µm, dual pixel PDAF, OIS, 10x optical zoom 12 MP, f/2.2, 13mm (ultrawide), 1/2.55", 1.4µm, dual pixel PDAF, Super Steady video
50 MP + 50 MP + 200 MP + 50 MP
Features
Laser AF, LED flash, auto-HDR, panorama
Laser AF, color spectrum sensor, Leica lenses, Dual-LED flash, HDR, panorama, 67mm filter ring holder (optional)
Video
8K@24fps, 4K@30/60fps, 1080p@30/60/120/240fps, HDR10+, stereo sound rec., gyro-EIS
8K@30fps, 4K@30/60/120fps, 1080p@30/60/120/240/480/960/1920fps, gyro-EIS, Dolby Vision HDR 10-bit rec. (4K@60fps, 1080p)
Memory 5 specs
Card slot
No
No
Internal
128GB 8GB RAM, 128GB 12GB RAM, 256GB 12GB RAM, 256GB 16GB RAM, 512GB 12GB RAM, 512GB 16GB RAM
256GB 12GB RAM, 512GB 16GB RAM, 1TB 16GB RAM
 
UFS 3.1
UFS 4.1
RAM
16GB
Storage
512GB
Misc 5 specs
Colors
Phantom Black, Phantom Silver, Phantom Titanium, Phantom Navy, Phantom Brown, Navy
Black, White, Silver Chrome, Green
Models
SM-G998B, SM-G998B/DS, SM-G998U, SM-G998U1, SM-G998W, SM-G998N, SM-G9980
25010PN30G
SAR
0.77 W/kg (head)     1.02 W/kg (body)    
SAR EU
0.71 W/kg (head)     1.58 W/kg (body)    
1.00 W/kg (head)     1.00 W/kg (body)    
Price
$ 254.95 / £ 214.99 / € 247.17
$ 693.75 / £ 1,295.00 / € 812.34
Network 7 specs
Technology
GSM / CDMA / HSPA / EVDO / LTE / 5G
GSM / HSPA / LTE / 5G
2G bands
GSM 850 / 900 / 1800 / 1900
GSM 850 / 900 / 1800 / 1900
 
1, 3, 5, 7, 8, 20, 28, 38, 40, 41, 66, 77, 78 SA/NSA/Sub6 - SM-G998B
1, 2, 3, 5, 7, 8, 12, 20, 26, 28, 38, 40, 41, 48, 66, 77, 78, 79, 80, 81, 83, 84, 89 SA/NSA - China
3G bands
HSDPA 850 / 900 / 1700(AWS) / 1900 / 2100
HSDPA 800 / 850 / 900 / 1700(AWS) / 1900 / 2100
4G bands
1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 18, 19, 20, 25, 26, 28, 30, 38, 39, 40, 41, 46, 48, 66, 71 - SM-G998U1
1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 18, 19, 20, 25, 26, 28, 32, 38, 39, 40, 41, 42, 48, 66, 71 - International
5G bands
2, 5, 25, 41, 66, 71, 260, 261 SA/NSA/Sub6/mmWave - SM-G998U1
1, 2, 3, 5, 7, 8, 12, 20, 25, 26, 28, 38, 40, 41, 48, 66, 71, 75, 77, 78, 79 SA/NSA - International
Speed
HSPA 42.2/5.76 Mbps, LTE (7CA) Cat20 2000/200 Mbps, 5G (5+ Gbps DL)
HSPA, LTE, 5G
Our Tests 6 specs
Performance
AnTuTu: 657150 (v8) GeekBench: 3518 (v5.1) GFXBench: 33fps (ES 3.1 onscreen)
Display
1023 nits max brightness (measured)
Camera
Photo / Video
Loudspeaker
-25.5 LUFS (Very good)
-24.1 LUFS (Very good)
Battery (old)
Endurance rating 114h
Battery
Active use score 16:13h
Platform 4 specs
OS
Android 11, up to 4 major Android upgrades, One UI 7
Android 15, HyperOS 2
Chipset
Exynos 2100 (5 nm) - InternationalQualcomm SM8350 Snapdragon 888 5G (5 nm) - USA/China
Snapdragon 8 Elite
CPU
Octa-core (1x2.9 GHz Cortex-X1 & 3x2.80 GHz Cortex-A78 & 4x2.2 GHz Cortex-A55) - InternationalOcta-core (1x2.84 GHz Cortex-X1 & 3x2.42 GHz Cortex-A78 & 4x1.80 GHz Cortex-A55) - USA/China
Octa-core (2x4.32 GHz Oryon V2 Phoenix L + 6x3.53 GHz Oryon V2 Phoenix M)
GPU
Mali-G78 MP14 - InternationalAdreno 660 - USA/China
Adreno 830
Selfie Camera 3 specs
Single
40 MP, f/2.2, 26mm (wide), 1/2.8", 0.7µm, PDAF
32 MP
Features
HDR
HDR, panorama
Video
4K@30/60fps, 1080p@30fps
4K@30/60fps, 1080p@30/60fps, gyro-EIS
Sound 3 specs
Loudspeaker
Yes, with stereo speakers
Yes, with stereo speakers
3.5mm jack
No
No
 
High-bitrate audio support
24-bit/192kHz Hi-Res & Hi-Res Wireless audio Qualcomm XPAN (24-bit/96kHz audio)
Eu Label 4 specs
Energy
Class A
Battery
58:58h endurance, 1000 cycles
Free fall
Class C (90 falls)
Repairability
Class C

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Common Questions

Which phone is the best in this comparison?

Samsung Galaxy S21 Ultra 5G has the bigger display.

How are the comparison winners decided?

We compare measurable specs (display size, battery capacity, RAM, charging, weight) and price (USD). When two phones tie or data is missing we mark the category "Depends".

Which is more affordable?

The cheaper option is shown as the value winner above. Prices are USD and may vary by region or retailer.