Xiaomi MI 9 vs. Microsoft Surface Duo

Phone Comparison, Reviews and Tests

In depth comparison and review of Xiaomi MI 9 and Microsoft Surface Duo. 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. Microsoft Surface Duo Comparison Chart
DESIGN AND DIMENSIONS Xiaomi MI 9 Microsoft Surface Duo
Product Type Smartphone Smartphone
Form Factor Touch Folder - dual screen
Height 157.5 mm 145.2 mm Xiaomi MI 9 has greater height than Microsoft Surface Duo.
Width 74.67 mm 93.3 mm Microsoft Surface Duo has greater width than Xiaomi MI 9.
Depth 7.61 mm 9.9 mm Xiaomi MI 9 is narrower than Xiaomi MI 9.
Weight 173 g 250 g Xiaomi MI 9 is lighter than Xiaomi MI 9.
Dimensions Details - Unfolded - 186.9 mm x 4.8 mm x 145.2 mm
Body Colour Ocean blue | Piano black Glacier
Body Material Curved glass -
Waterproof (Water-resistant) - -
SAR Value 1.301 W/kg (body), 1.389 W/kg (head) 0.726 W/kg (head), 1.478 W/kg (body)
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 Microsoft Surface Duo
Display Type OLED display OLED display
Display Technology AMOLED AMOLED
Foldable Display - Yes
Display Design - Both directions folding
Screen Size (Display Size) 6.39" 5.6" Xiaomi MI 9 has larger screen size than Microsoft Surface Duo.
Screen Resolution (Display Resolution) 2340 x 1080 pixels 1800 x 1350 pixels Xiaomi MI 9 has better screen resolution than Microsoft Surface Duo.
Display Format Full HD+ -
Pixel Density 403 ppi 401 ppi Xiaomi MI 9 has better pixel density than Microsoft Surface Duo.
Aspect Ratio - 4:3
Max Brightness 600 cd/m² -
Contrast Ratio 60000:1 -
HDR Yes - Xiaomi MI 9 has HDR.
HDR Technology HDR10 -
Display Enhancement Technology Sunshine mode 2.0 -
Display Features Always-on display, Reading mode, Colour temperature adjustment, night mode, Wide Colour Gamut (WCG) PixelSense Fusion Displays
Display Protection (Screen Protector) Fingerprint-resistant coating, Corning Gorilla Glass 6 (scratch resistant glass), oil protective coating Corning Gorilla Glass (scratch resistant glass)
SECOND DISPLAY
Second Display Type - OLED display - colour
Second Display Screen Size - 5.6"
Second Display Resolution - 1800 x 1350 pixels
UNFOLDED DISPLAY
Unfolded Display Screen Size - 8.1 in
Unfolded Display Resolution - 2700 x 1800 pixels
PROCESSOR Xiaomi MI 9 Microsoft Surface Duo
Processor Type (CPU) Qualcomm Snapdragon 855 Qualcomm Snapdragon 855
Clock Speed 2.84 GHz -
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 Microsoft Surface Duo
RAM LPDDR4X SDRAM - 6 GB 6 GB Both phones have the same RAM size.
Internal Memory Size (Storage Capacity) 64 GB 128 GB Microsoft Surface Duo has more internal memory than Xiaomi MI 9.
Memory Interface - UFS 3.0
CAMERA Xiaomi MI 9 Microsoft Surface Duo
MAIN CAMERA
Number of Main Cameras 3 0
Sensor Resolution 48 Megapixel -
Sensor Name Sony Exmor RS IMX586 sensor -
Lens Type Ultra wide-angle lens -
Lens Aperture F/1.75 -
Pixel Size 0.8 μm -
Focus Adjustment Automatic -
Laser Auto Focus Yes -
Optical Zoom 2x -
Digital Zoom 10x -
Special Effects HDR -
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 -
Face Recognition (Face ID) Face recognition - Xiaomi MI 9 has face detection.
Light Source Dual 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 -
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 -
SECOND CAMERA
Sensor Resolution (2nd Camera) 12 Megapixel -
Lens Type (2nd Camera) Telephoto lens -
Lens Aperture (2nd Camera) F/2.2 -
Pixel Size (2nd Camera) 1 μm -
Camera Features (2nd Camera) Macro photography -
THIRD CAMERA
Sensor Resolution (3rd Camera) 16 Megapixel -
Lens Type (3rd Camera) Ultra wide-angle lens -
Lens Aperture (3rd Camera) F/2.2 -
Pixel Size (3rd Camera) 1 μm -
FRONT CAMERA
Number of Front Cameras 1 1
Sensor Resolution (Front) 20 Megapixel 11 Megapixel Xiaomi MI 9 has better front camera resolution than Microsoft Surface Duo.
Lens Aperture (Front) F/2.0 F/2.0 Both phones have the same front camera lens aperture.
Field of View (Front) - 84 degree(s)
Pixel Size (Front) 0.9 μm 1 μm Microsoft Surface Duo has larger front camera pixel size than Xiaomi MI 9.
Special Effects (Front) HDR, Magic mirror HDR
Camera Modes (Front) AI portrait mode, AI Beautify, AI makeup Burst mode, Panorama, low-light shots, Portrait mode with adjustable depth control
Face Recognition (Face ID) Face recognition - Xiaomi MI 9 has face detection.
Light Source (Front) - High CRI LED flash
Video Resolutions (Front) 1920 x 1080 (1080p) at 30 fps, 1280 x 720 (720p) at 30 fps 1920 x 1080 (1080p) at 30 fps, 1920 x 1080 (1080p) at 60 fps, 3840 x 2160 (4K) at 30 fps, 3840 x 2160 (4K) at 60 fps
Camera Features (Front) Self-timer, age recognition, Video Beautify, AI scene detection, AI studio lighting, Eye light, AI feature adjustment, AI lens flare Phase Detect Auto-Focus (PDAF), FOV optimised with AI (for front and rear), dynamic range scene detection, Super-resolution zoom, super zoom up to 7x, gyro-based digital video stabilisation
BATTERY AND CHARGING Xiaomi MI 9 Microsoft Surface Duo
Battery Capacity (Battery Size) 3300 mAh 3577 mAh Microsoft Surface Duo has larger battery capacity than Xiaomi MI 9.
Fast Charging Technology Qualcomm Quick Charge 4.0+ - Xiaomi MI 9 has fast charging technology.
Wireless Charging Standards WPC, Qi -
Standby Time - 240 hours
Talk Time - 1620 minutes
Run Time Details - Standby: up to 240 hrs
Talk: up to 1620 min
Playback (local video): up to 15.5 hrs
CELLULAR Xiaomi MI 9 Microsoft Surface Duo
Technology CDMA2000 1X / GSM / WCDMA (UMTS) / TD-SCDMA WCDMA (UMTS) / GSM
Mobile Broadband Generation 4G 4G Both phones have the same mobile network generation.
Operating System - Android 10
User Interface MIUI 10 -
Intelligent Assistant Google Assistant Google Assistant
Payment Technology Android Pay -
Navigation GPS, A-GPS, GLONASS, BeiDou, Galileo GPS, GLONASS, BeiDou, Galileo, QZSS
COMMUNICATIONS Xiaomi MI 9 Microsoft Surface Duo
Data Transmission GPRS, EDGE, EV-DO, HSDPA, HSUPA, HSPA+, VoLTE, FDD-LTE, TDD-LTE GPRS, FDD-LTE, TDD-LTE, LAA
2G Band - 850 GSM, 900 GSM, 1800 GSM, 1900 GSM
3G UMTS Band Band 1, Band 2, Band 4, Band 5, Band 8 Band 1, Band 2, Band 5, Band 8
3G UMTS Frequency 2100, 1900, 1700, 850, 900 2100, 1900, 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 19, Band 20, Band 25, Band 26, Band 28, Band 29, Band 30, Band 38, Band 39, Band 40, Band 41, Band 46, Band 66
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 upper, FDD 800 DD, FDD 1900+, FDD 850+, FDD 700 APT, FDD 700d, FDD 2300 WCS, TDD 2600, TDD 1900, TDD 2300, TDD 2500, TDD 5150, FDD 1700 - 2110 AWS-3
Wireless Interface IEEE 802.11a/b/g/n/ac IEEE 802.11ac
Bluetooth Bluetooth 5.0 Bluetooth 5.0
NFC Yes - Xiaomi MI 9 has NFC reader for mobile payments.
WLAN Security WPA3 -
Messaging Services SMS, MMS -
MEDIA Xiaomi MI 9 Microsoft Surface Duo
Supported Digital Audio Standards WAV, AAC, AMR, MP3, FLAC, apt-X, LDAC, apt-X HD WAV, AAC, AMR, MP3, FLAC, OGG, MIDI, M4A, apt-X, IMY, RTTTL, RTX, OTA, MID
Supported Digital Video Standards MKV, VC-1, XviD, MPEG-4, H.264, M4V, HEVC, VP8, VP9 MKV, FLV, AVI, MOV, WMV, 3GP, TS, WebM, H.265 HEVC, MP4
Sound Enhancements Qualcomm TrueWireless Stereo Plus Qualcomm aptX audio
FEATURES Xiaomi MI 9 Microsoft Surface Duo
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 Proximity sensor, hall sensor, dual accelerometers, dual gyroscope, dual magnetometer, dual ambient light sensor
Security Devices Fingerprint reader (under display) Fingerprint reader (side)
Additional Phone Features Infrared remote control, MIMO technology, MU-MIMO technology, MI Turbo, GAME Turbo MIMO technology, Fast Charging, dual microphones with noise suppression and echo cancellation, Full Duplex communication, 360° hinge, stylus support, two apps side-by-side
OTHERS Xiaomi MI 9 Microsoft Surface Duo
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 headphones, 18W charger, Surface Duo Bumper (Glacier)
Compliant Standards TUV Rheinland Certified Safe Fast-Charge System -
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