Xiaomi Redmi Note 9 vs. Samsung Galaxy A21s

Phone Comparison, Reviews and Tests

In depth comparison and review of Xiaomi Redmi Note 9 and Samsung Galaxy A21s. 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 Redmi Note 9 vs. Samsung Galaxy A21s Comparison Chart
DESIGN AND DIMENSIONS Xiaomi Redmi Note 9 Samsung Galaxy A21s
Product Type Smartphone Smartphone
Manufacturer Model Number - SM-A217F/DSN
Form Factor Touch Touch
Height 162.3 mm 163.7 mm Samsung Galaxy A21s has greater height than Xiaomi Redmi Note 9.
Width 77.2 mm 75.3 mm Xiaomi Redmi Note 9 has greater width than Samsung Galaxy A21s.
Depth 8.9 mm 8.9 mm Both phones are the same depth.
Weight 199 g 192 g Samsung Galaxy A21s is lighter than Xiaomi Redmi Note 9.
Body Colour Forest green White | Blue | Black
Protection Splashproof -
Waterproof (Water-resistant) - -
SAR Value 2.262 W/kg (limb), 1.138 W/kg (body), 0.795 W/kg (head) 1.544 W/kg (body), 0.422 W/kg (head), 2.21 W/kg (limb)
Integrated Components Ultra-linear speaker -
Connector Type USB Type-C - 24 pin USB-C
Headset jack - mini-phone 3.5mm
USB Type-C - 24 pin USB-C
Headset jack - mini-phone 3.5mm
SIM Card Type (Size) Nano SIM Nano SIM
SIM Card Qty Dual-SIM Dual-SIM
SIM Card Configuration Details Nano SIM + nano SIM/microSD -
DISPLAY Xiaomi Redmi Note 9 Samsung Galaxy A21s
Display Type - LCD display
Display Technology - PLS TFT
Screen Size (Display Size) 6.53" 6.5" Xiaomi Redmi Note 9 has larger screen size than Samsung Galaxy A21s.
Screen Resolution (Display Resolution) 2340 x 1080 pixels 1600 x 720 pixels Xiaomi Redmi Note 9 has better screen resolution than Samsung Galaxy A21s.
Display Format Full HD+ HD+
Aspect Ratio 19.5:9 20:9
Max Brightness 450 cd/m² -
Colour Depth - 16.7 million colours
Contrast Ratio 1500:1 -
Display Features Reading mode 2.0, Dot Display, Full Screen gestures Infinity O display
Display Protection (Screen Protector) Corning Gorilla Glass 5 (scratch resistant glass) -
PROCESSOR Xiaomi Redmi Note 9 Samsung Galaxy A21s
Processor Type (CPU) MediaTek Helio G85 -
Clock Speed 2 GHz 2 GHz Both phones have the same clock speed.
Processor Core Qty 8-core 8-core Both phones have the same number of phone cores.
Graphics System (GPU) ARM G52 MC2 -
MEMORY Xiaomi Redmi Note 9 Samsung Galaxy A21s
RAM 3 GB 3 GB Both phones have the same RAM size.
Internal Memory Size (Storage Capacity) 64 GB 32 GB Xiaomi Redmi Note 9 has more internal memory than Samsung Galaxy A21s.
User Memory - 19.5 GB
Supported Flash Memory Cards (Expandable Memory) microSD microSDHC, microSDXC - up to 512 GB
CAMERA Xiaomi Redmi Note 9 Samsung Galaxy A21s
MAIN CAMERA
Number of Main Cameras 4 4
Sensor Resolution 48 Megapixel 48 Megapixel Both phones have the same camera resolution.
Sensor Size 1/2" -
Lens Type - Wide-angle lens
Lens Aperture F/1.79 F/2.0 Xiaomi Redmi Note 9 has better lens aperture than Xiaomi Redmi Note 9.
Lens Construction 6-element -
Field of View (FoV) 79.4 degree(s) 80 degree(s) Samsung Galaxy A21s has larger lens field of view than Xiaomi Redmi Note 9.
Pixel Size 0.8 μm -
Focus Adjustment Automatic Automatic
Digital Zoom - 8x
Special Effects HDR, Kaleidoscope -
Camera Modes Burst mode, Panorama, night mode, Smart ultra-wide angle mode, Photo timer, Custom watermark, Documents, Beautify, Levelling, Cinematic portraits Live Focus mode
Face Recognition (Face ID) Face recognition - Xiaomi Redmi Note 9 has face detection.
Light Source Flash LED flash
Video Resolutions 1920 x 1080 (1080p) at 30 fps, 1280 x 720 (720p) at 30 fps, Slo-mo video 1280 x 720 (720p) at 120 fps 1920 x 1080 (1080p) at 30 fps
Camera Features (Functions) 4-in-1 Super Pixel, AI scene detection, Portrait mode with background blurring, Ultra wide-angle edge distortion correction, Steady handheld night photography, full screen frame, AI watermark Live Focus
SECOND CAMERA
Sensor Resolution (2nd Camera) 8 Megapixel 8 Megapixel Both phones have the same second camera resolution.
Sensor Size (2nd Camera) 1/4" -
Lens Type (2nd Camera) Ultra wide-angle lens Ultra wide-angle lens
Lens Aperture (2nd Camera) F/2.2 F/2.2 Both phones have the same second camera lens aperture.
Lens Element Qty (2nd Camera) 5-element -
Field of View (2nd Camera) 118 degree(s) 123 degree(s) Samsung Galaxy A21s has larger second camera lens field of view than Xiaomi Redmi Note 9.
Pixel Size (2nd Camera) 1.2 μm -
Camera Features (2nd Camera) 5-piece lens -
THIRD CAMERA
Sensor Resolution (3rd Camera) 2 Megapixel 2 Megapixel Both phones have the same third camera resolution.
Lens Aperture (3rd Camera) F/2.4 F/2.4 Both phones have the same lens aperture of the third camera.
Pixel Size (3rd Camera) 1.75 μm -
Camera Functions (3rd Camera) Macro camera Macro camera
Camera Features (3rd Camera) AF (2cm-10cm) 4cm macro photography
FOURTH CAMERA
Sensor Resolution (4th Camera) 2 Megapixel 2 Megapixel Both phones have the same resolution of the fourth camera.
Sensor Size (4th Camera) 1/5" -
Lens Aperture (4th Camera) F/2.4 F/2.4 Both phones have the same lens aperture of the fourth camera.
Lens Element Qty (4th Camera) 3-element -
Pixel Size (4th Camera) 1.75 μm -
Camera Functions (4th Camera) Depth camera Depth camera
FRONT CAMERA
Number of Front Cameras 1 1
Sensor Resolution (Front) 13 Megapixel 13 Megapixel Both phones have the same front camera resolution.
Sensor Size (Front) 1/3.06" -
Lens Aperture (Front) F/2.25 F/2.2 Samsung Galaxy A21s has better front lens aperture than Xiaomi Redmi Note 9.
Lens Element Qty (Front) 5-element -
Field of View (Front) 74 degree(s) -
Pixel Size (Front) 1.12 μm -
Focus Adjustment - Focus free
Special Effects (Front) HDR -
Camera Modes (Front) Panoramic selfies, AI portrait mode, AI Beautify -
Face Recognition (Face ID) Face recognition - Xiaomi Redmi Note 9 has face detection.
Light Source (Front) Display flash -
Camera Features (Front) Palm shutter, AI silhouette detection -
BATTERY AND CHARGING Xiaomi Redmi Note 9 Samsung Galaxy A21s
Battery Capacity (Battery Size) 5020 mAh 5000 mAh Xiaomi Redmi Note 9 has larger battery capacity than Samsung Galaxy A21s.
Talk Time 1980 minutes 3240 minutes Samsung Galaxy A21s has longer battery life when making calls than Xiaomi Redmi Note 9.
Run Time Details Talk: up to 1980 min
Gaming: up to 16 hrs
Playback (Music): up to 147 hrs
Navigation: up to 16 hrs
Active online usage (4G): up to 23 hrs
Active online usage (Wi-Fi): up to 23 hrs
Playback (video): up to 21 hrs
Playback (audio): up to 109 hrs
Talk (4G): up to 3240 min
Battery Technology Lithium polymer Lithium Ion
CELLULAR Xiaomi Redmi Note 9 Samsung Galaxy A21s
Technology WCDMA (UMTS) / GSM WCDMA (UMTS) / GSM
Mobile Broadband Generation 4G 4G Both phones have the same mobile network generation.
User Interface - One UI
Navigation GPS, A-GPS, GLONASS, BeiDou, Galileo GPS, GLONASS, BeiDou, Galileo
COMMUNICATIONS Xiaomi Redmi Note 9 Samsung Galaxy A21s
Data Transmission VoLTE, FDD-LTE, TDD-LTE GPRS, EDGE, HSDPA, HSUPA, HSPA+, FDD-LTE, TDD-LTE
2G Band 850 GSM, 900 GSM, 1900 GSM, 2100 GSM 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 20, Band 28, Band 38, Band 40, Band 41 Band 1, Band 2, Band 3, Band 5, Band 7, Band 8, Band 20, Band 28, Band 38, Band 40, Band 41
4G LTE Frequency FDD 2100, FDD 1900 PCS, FDD 1800+, FDD 1700 - 2110 AWS, FDD 850, FDD 2600, FDD 900, FDD 800 DD, FDD 700 APT, TDD 2600, TDD 2300, TDD 2500 FDD 2100, FDD 1900 PCS, FDD 1800+, FDD 850, FDD 2600, FDD 900, FDD 800 DD, FDD 700 APT, TDD 2600, TDD 2300, TDD 2500
Wireless Interface IEEE 802.11a/b/g/n/ac IEEE 802.11a/b/g/n/ac
Bluetooth Bluetooth 5.0 Bluetooth 5.0 LE
NFC - Yes Samsung Galaxy A21s has NFC reader for mobile payments.
Messaging Services - SMS, MMS
MEDIA Xiaomi Redmi Note 9 Samsung Galaxy A21s
Supported Digital Audio Standards WAV, AAC, AMR, MP3, FLAC, APE (Monkey's Audio) WAV, WMA, AAC, AMR, MP3, FLAC, XMF, OGG, MIDI, M4A, MXMF, OGA, 3GA, AWB, IMY, RTTTL, RTX, OTA, MID
Supported Digital Video Standards MKV, XviD, M4V, MP4 MKV, FLV, AVI, WMV, ASF, 3GP, M4V, WebM, 3G2, MP4
Sound Enhancements - Dolby Atmos sound technology
Audio Amplifier Smart PA -
FEATURES Xiaomi Redmi Note 9 Samsung Galaxy A21s
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, proximity sensor, digital compass, gyro sensor, infrared (IR) sensor Accelerometer, proximity sensor, gyro sensor, geomagnetic sensor
Security Devices Face recognition, fingerprint reader Face recognition, fingerprint reader
Additional Phone Features Infrared remote control, HyperEngine technology Samsung KNOX, Virtual Light Sensing
OTHERS Xiaomi Redmi Note 9 Samsung Galaxy A21s
Included Accessories Protective cover, power adapter, SIM card removal tool, USB-C cable Power adapter
Compliant Standards TUV Rheinland Low Blue Light Certification -
Other projects: