Xiaomi MI 9 vs. Samsung Galaxy S21 5G

Phone Comparison, Reviews and Tests

In depth comparison and review of Xiaomi MI 9 and Samsung Galaxy S21 5G. Compare sizes, cameras, batteries, memory, and other important specifications and features to easily choose the right phone for you. Our goal is to help you uncover differences between the products and find the phone that will best fit your needs.

Phone Specifications Comparison

Xiaomi MI 9 vs. Samsung Galaxy S21 5G Comparison Chart
DESIGN AND DIMENSIONS Xiaomi MI 9 Samsung Galaxy S21 5G
Product Type Smartphone Smartphone
Manufacturer Model Number - SM-G991U1
Form Factor Touch Touch
Height 157.5 mm 151.7 mm Xiaomi MI 9 has greater height than Samsung Galaxy S21 5G.
Width 74.67 mm 71.2 mm Xiaomi MI 9 has greater width than Samsung Galaxy S21 5G.
Depth 7.61 mm 7.9 mm Xiaomi MI 9 is narrower than Xiaomi MI 9.
Weight 173 g 171 g Samsung Galaxy S21 5G is lighter than Xiaomi MI 9.
Body Colour Ocean blue | Piano black Phantom grey | Phantom white
Body Material Curved glass -
Protection - Dustproof, splashproof, water-resistant
Waterproof (Water-resistant) - Yes Samsung Galaxy S21 5G is waterproof.
IP rating - IP68
SAR Value 1.301 W/kg (body), 1.389 W/kg (head) 1.58 W/kg (simultaneous), 1.11 W/kg (wireless router), 1.08 W/kg (body), 0.74 W/kg (head)
Connector Type USB Type-C - 24 pin USB-C USB Type-C - 24 pin USB-C
SIM Card Type (Size) Nano SIM Nano SIM, Electronic SIM card (e-SIM)
SIM Card Qty Dual-SIM Dual-SIM
DISPLAY Xiaomi MI 9 Samsung Galaxy S21 5G
Display Type OLED display OLED display
Display Technology AMOLED Infinity-O Dynamic AMOLED 2X
Screen Size (Display Size) 6.39" 6.2" Xiaomi MI 9 has larger screen size than Samsung Galaxy S21 5G.
Screen Resolution (Display Resolution) 2340 x 1080 pixels 2400 x 1080 pixels Samsung Galaxy S21 5G has better screen resolution than Xiaomi MI 9.
Display Format Full HD+ Full HD+
Pixel Density 403 ppi 421 ppi Samsung Galaxy S21 5G has better pixel density than Xiaomi MI 9.
Max Brightness 600 cd/m² -
Colour Depth - 16.7 million colours
Contrast Ratio 60000:1 -
HDR Yes Yes Both phones have HDR.
HDR Technology HDR10 HDR10+
Display Enhancement Technology Sunshine mode 2.0 Eye Comfort Shield
Display Refresh Rate - 120 Hz
Display Features Always-on display, Reading mode, Colour temperature adjustment, night mode, Wide Colour Gamut (WCG) AOD(Always On Display), Video Wallpaper
Display Protection (Screen Protector) Fingerprint-resistant coating, Corning Gorilla Glass 6 (scratch resistant glass), oil protective coating Corning Gorilla Glass Victus (scratch resistant glass)
PROCESSOR Xiaomi MI 9 Samsung Galaxy S21 5G
Processor Type (CPU) Qualcomm Snapdragon 855 Qualcomm Snapdragon 888
Clock Speed 2.84 GHz 2.84 GHz Both phones have the same clock speed.
Processor Core Qty 8-core 8-core Both phones have the same number of phone cores.
64-bit Architecture Yes - Xiaomi MI 9 has 64-bit architecture.
Graphics System (GPU) Qualcomm ADRENO 640 -
MEMORY Xiaomi MI 9 Samsung Galaxy S21 5G
RAM LPDDR4X SDRAM - 6 GB LPDDR5 SDRAM - 8 GB Samsung Galaxy S21 5G has more RAM than Xiaomi MI 9.
Internal Memory Size (Storage Capacity) 64 GB 128 GB Samsung Galaxy S21 5G has more internal memory than Xiaomi MI 9.
User Memory - 101.2 GB
CAMERA Xiaomi MI 9 Samsung Galaxy S21 5G
MAIN CAMERA
Number of Main Cameras 3 3
Sensor Resolution 48 Megapixel 12 Megapixel Xiaomi MI 9 has better camera resolution than Samsung Galaxy S21 5G.
Sensor Size - 1/1.76"
Sensor Name Sony Exmor RS IMX586 sensor -
Lens Type Ultra wide-angle lens Wide-angle lens
Lens Aperture F/1.75 F/1.8 Xiaomi MI 9 has better lens aperture than Xiaomi MI 9.
Field of View (FoV) - 79 degree(s)
Pixel Size 0.8 μm 1.8 μm Samsung Galaxy S21 5G has larger camera pixel size than Xiaomi MI 9.
Optical Image Stabiliser (OIS) - Optical Image Stabiliser (OIS) Samsung Galaxy S21 5G has optical stabilisation.
Focus Adjustment Automatic Automatic
Laser Auto Focus Yes Yes
Optical Zoom 2x 3x Samsung Galaxy S21 5G has better optical zoom than Xiaomi MI 9.
Digital Zoom 10x 30x Samsung Galaxy S21 5G has better digital zoom than Xiaomi MI 9.
Self-Timer Delay - Yes
Special Effects HDR Face retouch, Grid Line
HDR Mode - Auto HDR mode
Camera Modes Burst mode, Panorama, portrait mode, AI Beautify, Smart ultra-wide angle mode, Ultra nightscape mode, Photo timer, Level display, Custom watermark, Full body portrait mode, Moon mode Panorama, Slow motion mode, Pro mode, HYPERLAPSE, Super Slow-mo, Flowers, Greenery, Trees, Sky, Beaches, Watersides, Snow, Backlit, Text, Food, Face, Baby, Person, Dog, Cat, People, Sunset, Sunrise, City, Waterfall, Scenery, Stage, Vehicles, Drinks, Animal, Shoes, Indoor, Clothes, Night view, Portrait, Night, Motion Photo, Mountain, Single Take, Pro Video, Portrait video, Director's View
Face Recognition (Face ID) Face recognition - Xiaomi MI 9 has face detection.
Light Source Dual flash High CRI LED flash
Still Image Resolutions 8000 x 6000 -
Video Resolutions 1920 x 1080 (1080p) at 30 fps, 1920 x 1080 (1080p) at 60 fps, 1280 x 720 (720p) at 30 fps, Slo-mo video 1920 x 1080 (1080p) at 120 fps, Slo-mo video 1280 x 720 (720p) at 240 fps, 3840 x 2160 (4K) at 30 fps, Slo-mo video 1280 x 720 (720p) at 120 fps, 3840 x 2160 (4K) at 60 fps, Slo-mo video 1920 x 1080 (1080p) at 240 fps, Slo-mo video 1920 x 1080 (1080p) at 960 fps, Slo-mo video 1280 x 720 (720p) at 960 fps 1920 x 1080 (1080p) at 60 fps, 1280 x 720 (720p) at 30 fps, 3840 x 2160 (4K) at 60 fps, Super slow motion video 1280 x 720 (720p) at 960 fps, Slo-mo video 1920 x 1080 (1080p) at 240 fps, 7680 x 4320 (8K) at 24 fps, Hyperlapse 4K video support at 30 fps, Super Steady 1080p video support at 60 fps
Camera Features (Functions) Sapphire crystal lens cover, Phase Detect Auto-Focus (PDAF), Dynamic photos, video stabilisation, Contrast Auto-Focus, AI scene detection, AI studio lighting, Video Beautify, AI Triple camera, 960 fps Smart audio pairing, AI lens flare, AI high resolution photos, Portrait mode background blur adjustment, Ultra wide-angle edge distortion correction, Group photo face correction, Portrait mode background blurring, Motion tracking, Quick motion Playback zoom, Motion photo, blink detection, QR-code scanner, VDIS (Video Digital Image Stabilisation), Tracking AF, Video location tags, Scene Optimiser, Lens smudge, Flaw detection, Shot suggestions, blur detection, HDR10+ recording, Super steady, Super Speed Dual Pixel AF, Quick Measure, Zoom-In Mic, HEIF image capture, Space Zoom, Take 33MP still photos while playing 8K video, Hybrid Optic Zoom 3x, Super Resolution Zoom up to 30x, Digital zoom up to 12x for video, AR Doodle, HEVC (High Efficiency Video coding) support, Microphone Control (Pro Video only)
SECOND CAMERA
Sensor Resolution (2nd Camera) 12 Megapixel 12 Megapixel Both phones have the same second camera resolution.
Lens Type (2nd Camera) Telephoto lens Ultra wide-angle lens
Lens Aperture (2nd Camera) F/2.2 F/2.2 Both phones have the same second camera lens aperture.
Field of View (2nd Camera) - 120 degree(s)
Pixel Size (2nd Camera) 1 μm 1.4 μm Samsung Galaxy S21 5G has larger second camera pixel size than Xiaomi MI 9.
Camera Features (2nd Camera) Macro photography -
THIRD CAMERA
Sensor Resolution (3rd Camera) 16 Megapixel 64 Megapixel Samsung Galaxy S21 5G has higher resolution third camera than Xiaomi MI 9.
Sensor Size (3rd Camera) - 1/1.72"
Lens Type (3rd Camera) Ultra wide-angle lens Telephoto lens
Lens Aperture (3rd Camera) F/2.2 F/2.0 Samsung Galaxy S21 5G has better third camera lens aperture than Xiaomi MI 9.
Field of View (3rd Camera) - 76 degree(s)
Pixel Size (3rd Camera) 1 μm 0.8 μm Xiaomi MI 9 has larger third camera pixel size than Samsung Galaxy S21 5G.
Optical Image Stabiliser (OIS) - Optical Image Stabiliser (OIS) Samsung Galaxy S21 5G has optical stabilisation of the third camera.
FRONT CAMERA
Number of Front Cameras 1 1
Sensor Resolution (Front) 20 Megapixel 10 Megapixel Xiaomi MI 9 has better front camera resolution than Samsung Galaxy S21 5G.
Lens Aperture (Front) F/2.0 F/2.2 Xiaomi MI 9 has better front lens aperture than Xiaomi MI 9.
Field of View (Front) - 80 degree(s)
Pixel Size (Front) 0.9 μm 1.22 μm Samsung Galaxy S21 5G has larger front camera pixel size than Xiaomi MI 9.
Focus Adjustment - Automatic
Special Effects (Front) HDR, Magic mirror -
Camera Modes (Front) AI portrait mode, AI Beautify, AI makeup -
Face Recognition (Face ID) Face recognition - Xiaomi MI 9 has face detection.
Video Resolutions (Front) 1920 x 1080 (1080p) at 30 fps, 1280 x 720 (720p) at 30 fps -
Camera Features (Front) Self-timer, age recognition, Video Beautify, AI scene detection, AI studio lighting, Eye light, AI feature adjustment, AI lens flare Dual Pixel AF
BATTERY AND CHARGING Xiaomi MI 9 Samsung Galaxy S21 5G
Battery Capacity (Battery Size) 3300 mAh 4000 mAh Samsung Galaxy S21 5G has larger battery capacity than Xiaomi MI 9.
Fast Charging Technology Qualcomm Quick Charge 4.0+ Qualcomm Quick Charge 2.0, Adaptive Fast Charging, Power Delivery 3.0 Both phones have fast charging technology.
Wireless Charging - Yes Samsung Galaxy S21 5G can be charged wirelessly.
Wireless Charging Standards WPC, Qi WPC, Qi, Fast Wireless Charging 2.0, Wireless PowerShare
Talk Time - 1800 minutes
Run Time Details - Talk (LTE): up to 1800 min
Active online usage (LTE): up to 14 hrs
Active online usage (Wi-Fi): up to 15 hrs
Playback (wireless video): up to 19 hrs
Playback (wireless audio): up to 72 hrs
CELLULAR Xiaomi MI 9 Samsung Galaxy S21 5G
Technology CDMA2000 1X / GSM / WCDMA (UMTS) / TD-SCDMA CDMA2000 1X / GSM / WCDMA (UMTS)
Mobile Broadband Generation 4G 5G Samsung Galaxy S21 5G has more advanced generation mobile network.
Operating System - Android 11
User Interface MIUI 10 -
Intelligent Assistant Google Assistant Bixby
Payment Technology Android Pay Samsung Pay
Navigation GPS, A-GPS, GLONASS, BeiDou, Galileo GPS, GLONASS, Galileo
COMMUNICATIONS Xiaomi MI 9 Samsung Galaxy S21 5G
Data Transmission GPRS, EDGE, EV-DO, HSDPA, HSUPA, HSPA+, VoLTE, FDD-LTE, TDD-LTE FDD-LTE, TDD-LTE, 5G NR FR1, 5G NR FR2
2G Band - 850 GSM, 900 GSM, 1800 GSM, 1900 GSM, 800 CDMA2000 1X, 1900 CDMA2000 1X
3G UMTS Band Band 1, Band 2, Band 4, Band 5, Band 8 Band 1, Band 2, Band 4, Band 5, Band 8
3G UMTS Frequency 2100, 1900, 1700, 850, 900 2100, 1900, 1700, 850, 900
4G LTE Band Band 1, Band 2, Band 3, Band 4, Band 5, Band 7, Band 8, Band 12, Band 20, Band 28, Band 38, Band 39, Band 40 Band 1, Band 2, Band 3, Band 4, Band 5, Band 7, Band 8, Band 12, Band 13, Band 14, Band 18, Band 19, Band 20, Band 25, Band 26, Band 28, Band 30, Band 38, Band 39, Band 40, Band 41, Band 46, Band 48, Band 66, Band 71
4G LTE Frequency FDD 2100, FDD 1900 PCS, FDD 1800+, FDD 1700 - 2110 AWS, FDD 850, FDD 2600, FDD 900, FDD 700a, FDD 800 DD, FDD 700 APT, TDD 2600, TDD 1900, TDD 2300 FDD 2100, FDD 1900 PCS, FDD 1800+, FDD 1700 - 2110 AWS, FDD 850, FDD 2600, FDD 900, FDD 700a, FDD 700c, FDD 700 PS, FDD 800 lower, FDD 800 upper, FDD 800 DD, FDD 1900+, FDD 850+, FDD 700 APT, FDD 2300 WCS, TDD 2600, TDD 1900, TDD 2300, TDD 2500, TDD 5150, TDD 3600, FDD 1700 - 2110 AWS-3, FDD 600
5G NR Band - N41, n71, n260, n261
5G NR Frequency - TDD TD 2500, FDD 600, TDD 39GHz, TDD 28GHz
Wireless Interface IEEE 802.11a/b/g/n/ac IEEE 802.11a/b/g/n/ac/ax
Bluetooth Bluetooth 5.0 Bluetooth 5.0
NFC Yes Yes Both phones have an NFC reader for mobile payments.
WLAN Security WPA3 -
Messaging Services SMS, MMS -
MEDIA Xiaomi MI 9 Samsung Galaxy S21 5G
Supported Digital Audio Standards WAV, AAC, AMR, MP3, FLAC, apt-X, LDAC, apt-X HD WAV, AAC, PCM, AMR, MP3, FLAC, XMF, OGG, MIDI, APE (Monkey's Audio), M4A, DSF, MXMF, OGA, 3GA, AWB, IMY, RTTTL, RTX, OTA, DFF, MID, DSD64, DSD128
Supported Digital Video Standards MKV, VC-1, XviD, MPEG-4, H.264, M4V, HEVC, VP8, VP9 MKV, FLV, AVI, 3GP, M4V, WebM, 3G2, MP4
Sound Enhancements Qualcomm TrueWireless Stereo Plus Dolby Digital Plus sound, Dolby Atmos sound technology, Surround sound, stereo speakers tuned by AKG, Dolby Digital sound
FEATURES Xiaomi MI 9 Samsung Galaxy S21 5G
Phone Functions Speakerphone, voice control, call timer, conference call, flight mode, voice dialing, vibrating alert Speakerphone, voice control, call timer, conference call, flight mode, voice dialing, vibrating alert
Sensors Accelerometer, ambient light sensor, digital compass, gyro sensor, ultrasonic proximity sensor, linear rotation vector sensor Accelerometer, ambient light sensor, proximity sensor, barometer, gyro sensor, hall sensor, geomagnetic sensor
Security Devices Fingerprint reader (under display) Fingerprint reader (under display), face recognition
Additional Phone Features Infrared remote control, MIMO technology, MU-MIMO technology, MI Turbo, GAME Turbo MIMO technology, Screen Write, notification flashlight, Smart Select, Fast Charging, Samsung KNOX, Smart View, Live message, Screen off memo, Samsung DeX support, Bixby Vision, TalkBack, Dual Audio, Bixby Routines, Intelligent Performance Enhancer, Bixby key, Bluetooth Scalable Codec, Samsung Knox Vault, Private Share function, Enhanced Game Booster, Air Command
OTHERS Xiaomi MI 9 Samsung Galaxy S21 5G
Included Accessories Protective cover, SIM card removal tool, USB-C cable, USB-C audio adapter, 18W QC3.0 charger SIM card removal tool, USB-C to USB-C cable
Compliant Standards TUV Rheinland Certified Safe Fast-Charge System VDE, IP68, HAC (Hearing Aid Compatible), SGS Eye Care Display Certification
Max Depth of Water Resistance - 1.5 m
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