Samsung Galaxy A51 vs Xiaomi Redmi 9 Specs Comparison

Availability

Officially announced
Dec 12, 2019
Prices (MSRP)
$400

Design

Dimensions
6.24 x 2.90 x 0.31 inches 158.5 x 73.6 x 7.9 mm	6.43 x 3.03 x 0.36 inches 163.32 x 77.01 x 9.1 mm
Weight
6.07 oz / 172.0 g	6.98 oz / 198.0 g
Materials
Back: Plastic Frame: Plastic
Biometrics
2D Face unlock, Optical in-screen fingerprint	2D Face unlock, Fingerprint (touch)
Keys
Right: Volume control, Lock/Unlock key	Right: Volume control, Lock/Unlock key
Colors
Prism Crush black, Prism Crush white, Prism Crush pink, Prism Crush blue	Carbon gray, Sunset purple, Ocean green

Display

Size
6.5-inch, 87.37% screen-to-body	6.5-inch, 83.27% screen-to-body
Type
Super AMOLED, 60Hz	IPS LCD
Resolution
2400x1080px, 20:9 ratio, 405 PPI	2340x1080px, 19.5:9 ratio, 395 PPI
Protection
Corning Gorilla Glass 3	Corning Gorilla Glass 3
Features
	Oleophobic coating

PhoneArena Display Test

Bright Max (20% APL)
Untested	Untested
Bright Min
1.7 (Good)	1.5 (Good)

Learn more on our PhoneArena Display Test Results page.

Hardware

System chip
Samsung Exynos 9611 (10 nm)	MediaTek Helio G80 (12 nm)
Processor
Octa-core 2300 MHz 4x2.3GHz Cortex-A73 4x1.7G​Hz Cortex-A53	Octa-core 2000 MHz Arm Cortex-A75 and Arm Cortex-A55
GPU
Mali-G72 MP3	Mali G52 MC2
Memory
4GB (LPDDR4)/128GB 6GB/128GB	3GB (LPDDR4)/32GB (eMMC 5.1) 4GB/64GB
Storage expansion
microSDXC up to 512 GB	microSDXC
OS
Android (11, 10)	Android

Battery

Type
4000 mAh, Li - Polymer	5020 mAh
Charging
Fast charging	Qualcomm Quick Charge 3.0
Charge speed
	Wired: 18.0W

PhoneArena Battery Tests

Battery Life Estimate

5h 22min

Browsing

11h 35min

Video

8h 35min

Gaming

6h 40min

Battery Life Estimate

Untested

Browsing

Untested

Video

9h 15min

Gaming

7h 3min

Learn more on our PhoneArena Battery Test Results page

Camera

Rear
Quad camera	Quad camera
Main camera
48 MP (PDAF) Aperture size: F2.0 Focal length: 26 mm Sensor size: 1/2" Pixel size: 0.8 μm	13 MP (PDAF) Aperture size: F2.2
Second camera
12 MP (Ultra-wide) Aperture size: F2.2 Focal Length: 13 mm Pixel size: 1.12 μm	8 MP (Ultra-wide) Aperture size: F2.2
Third camera
5 MP (Macro) Aperture size: F2.4 Focal Length: 40 mm	5 MP (Macro) Aperture size: F2.4
Fourth camera
5 MP (Depth information) Aperture size: F2.2 Sensor size: 1/5" Pixel size: 1.12 μm	2 MP (Depth information)
Flash
LED	LED
Video recording
4K UHD (30 fps), 1080p (120 fps), 720p (240 fps) Hyperlapse, EIS	1080p
Front
32 MP (HDR) Video capture: 1080p	8 MP (HDR) Video capture: 1080p

Connectivity & Features

Bluetooth
5.0	5.0
WLAN
a,b,g,n,ac,dual-band Wi-Fi Direct, Hotspot 802.11 a, b, g, n, ac	b,g,n Wi-Fi Direct, Hotspot 802.11 b, g, n
USB
Type-C, USB 2.0	Type-C, USB 2.0
Sensors
Accelerometer, Gyroscope, Compass, Hall (for flip covers), Ambient light sensor, Proximity sensor	Accelerometer, Gyroscope, Compass, Ambient light sensor, Proximity sensor
Location
GPS, A-GPS, Glonass, Galileo, BeiDou, Cell ID, Wi-Fi positioning	GPS, A-GPS, Glonass, BeiDou, Cell ID, Wi-Fi positioning
Other
NFC, ANT+	NFC, Infrared

Multimedia

Headphones
3.5mm jack	3.5mm jack
Speakers
Earpiece, Loudspeaker	Earpiece, Loudspeaker
Features
Dolby Atmos
Screen mirroring
Wireless screen share	Wireless screen share
Radio
FM	FM
Additional microphone(s)
Noise cancellation	Noise cancellation

Cellular

4G (FDD) Bands
1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 20, 25, 26, 28, 29, 30, 66, 71	1, 2, 3, 4, 5, 7, 8, 20, 28
4G (TDD) Bands
38, 39, 41	38, 40, 41
3G Bands
1, 2, 4, 5, 8	1, 2, 4, 5, 8
Data Speed
LTE-A, HSDPA+ (4G) 42.2 Mbit/s, HSUPA 5.76 Mbit/s	LTE-A, HSDPA+ (4G) 42.2 Mbit/s, HSUPA 5.76 Mbit/s
Dual SIM
	Yes
SIM type
Nano SIM	Nano SIM
HD Voice
	Yes
VoLTE
	Yes

Regulatory Approval

FCC approval
Date approved: Nov 28, 2019 FCC ID value: A3LSMA515FN
Measured SAR
Head: 0.89 W/kg Body: 1.18 W/kg Simultaneous Transmission: 1.56 W/kg Wireless Router: 1.12 W/kg Phablet: 2.76 W/kg

Alternative variants

with 128GB storage

Memory	6GB/128GB

with 64GB storage

Memory	4GB/64GB

for Verizon

4G (FDD) Bands	2, 3, 4, 5, 7, 13, 20, 28, 66
3G Bands	5, 8, 2, 1

for AT&T

4G (FDD) Bands	2, 4, 5, 12, 13, 25, 26, 66, 71
4G (TDD) Bands	41

for Sprint

4G (FDD) Bands	2, 4, 5, 12, 13, 25, 26, 66, 71
4G (TDD) Bands	41

for Europe

4G (FDD) Bands	1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 20, 26, 28, 66
4G (TDD) Bands	38, 40, 41
Dual SIM	Yes

Links

Full specifications
Samsung Galaxy A51 Specs	Xiaomi Redmi 9 Specs
PhoneArena Review
Samsung Galaxy A51 Review	Xiaomi Redmi 9 Review
User Reviews
Samsung Galaxy A51 User Reviews	Xiaomi Redmi 9 User Reviews