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Samsung Galaxy A51 vs Redmi K20

Key Feature Comparison

6.9

Samsung Galaxy A51

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Redmi K20

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At a Glance

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Octa core (2.3 GHz, Quad core, Cortex A73 + 1.7 GHz, Quad core, Cortex A53)

Samsung Exynos 9 Octa 9611, Mali-G72 MP3

Octa core (2.2 GHz, Dual core, Kryo 470 + 1.8 GHz, Hexa Core, Kryo 470)

Qualcomm Snapdragon 730, Adreno 618

4000 mAh

Li-ion, Fast, 15W

4000 mAh

Li-Polymer, Quick, v3.0, 18W

16.51 cm (6.5 inch)

405 ppi, FHD

16.23 cm (6.4 inch)

403 ppi, FHD

Quad, 48MP + 12MP + 5MP + 5MP

3840x2160 @ 30 fps

Triple, 48MP + 13MP + 8MP

3840x2160 @ 30 fps, 1920x1080 @ 60 fps, 1280x720 @ 120 fps

4G

Dual SIM, GSM+GSM

4G

Dual SIM, GSM+GSM, Dual VoLTE

Detailed Specs

Screen Size

16.51 cm (6.5 inch)
16.23 cm (6.4 inch)

Screen Type

Super AMOLED
AMOLED

Screen Resolution

1080 x 2400 pixels
1080 x 2340 pixels

Pixel Density

405 ppi
403 ppi

Aspect Ratio

20:09
19.5:9

Screen Protection

Gorilla Glass 3
Gorilla Glass 5

Screen to Body Ratio

87.44%
91.90%

Screen Design

Punch hole
Bezel-less

Screen Quality

FHD
FHD

Phone Variants

8GB 128GB, 6GB 128GB
6GB 128GB, 6GB 64GB

Expandable Storage

Yes
No

RAM Type

LPDDR4X
LPDDR4X

Storage Type

UFS 2.0
UFS 2.1

Expandable Storage Capacity

Yes, 512 GB
-

OTG Support

Yes
Yes

Sensors

Light sensor, Proximity sensor, Accelerometer, Gyroscope
Light sensor, Proximity sensor, Accelerometer, Compass, Gyroscope

Operating System

Android v10 (Q)
Android v9.0 (Pie)

GPU

Mali-G72 MP3
Adreno 618

Chipset

Samsung Exynos 9 Octa 9611
Qualcomm Snapdragon 730

CPU

Octa core (2.3 GHz, Quad core, Cortex A73 + 1.7 GHz, Quad core, Cortex A53)
Octa core (2.2 GHz, Dual core, Kryo 470 + 1.8 GHz, Hexa Core, Kryo 470)

Custom User Interface

Samsung One UI
MIUI

Clock Speed

2.3 GHz
2.2 GHz

Architecture

64 bit
64 bit

Process Technology

10 nm
8 nm

Battery Capacity

4000 mAh
4000 mAh

Battery Removable

No
No

Battery Type

Li-ion
Li-Polymer

Charger Type

Fast, 15W
Quick, v3.0, 18W

USB Type-C

Yes
Yes

Fast Charging

Yes
Yes

Announced On

5-Dec-19
5-May-19

Market Status

Available
Available

Brand

Samsung
Xiaomi

Model Number

SM-A515FZB1INS/SM-A515FZBWINS
MZB7756IN

Price Status

Confirmed
Confirmed

Price

Rs. 20,450
Rs. 19,450

GPS

Yes A-GPS, Glonass
Yes A-GPS, Glonass

Audio Features

Dolby Atmos
24-bit/192kHz audioActive noise cancellation with dedicated mic

NFC

Yes
Yes

Network Support

4G
4G

Bluetooth

Yes
Yes

3.5mm Audio Jack

Yes
Yes

SIM Size

SIM1: Nano, SIM2: Nano
SIM1: Nano, SIM2: Nano

Wi-Fi

Yes, Wi-Fi 802.11, ac/b/g/n/n 5GHz
Yes, Wi-Fi 802.11, ac/b/g/n, MIMO

Bluetooth Type

v5.0
v5.0

Audio Jack

3.5 mm
3.5 mm

SIM Slot(s)

Dual SIM, GSM+GSM
Dual SIM, GSM+GSM, Dual VoLTE

eSIM

No
No

Wi-Fi Features

Wi-Fi Direct, Mobile Hotspot
Wi-Fi Direct, Mobile Hotspot

VoLTE

Yes
Yes

SIM 1 Bands

4G Bands: TD-LTE 2600(band 38) / 2300(band 40) / 2500(band 41), FD-LTE 2100(band 1) / 1800(band 3) / 2600(band 7) / 700(band 28) / 1900(band 2) / 1700(band 4) / 850(band 5) / 700(band 13) / 700(band 17) / 800(band 20) / 850(band 26), 3G Bands: UMTS 1...
4G Bands: TD-LTE 2600(band 38) / 2300(band 40) / 2500(band 41), FD-LTE 2100(band 1) / 1800(band 3) / 2600(band 7) / 900(band 8) / 850(band 5), 3G Bands: UMTS 1900 / 2100 / 850 / 900 MHz, 2G Bands: GSM 1800 / 1900 / 850 / 900 MHz, GPRS: Available, EDG...

SIM 2 Bands

4G Bands: TD-LTE 2600(band 38) / 2300(band 40) / 2500(band 41), FD-LTE 2100(band 1) / 1800(band 3) / 2600(band 7) / 900(band 8) / 700(band 28) / 1900(band 2) / 1700(band 4) / 850(band 5) / 700(band 13) / 700(band 17) / 800(band 20) / 850(band 26), 3G...
4G Bands: TD-LTE 2600(band 38) / 2300(band 40) / 2500(band 41), FD-LTE 2100(band 1) / 1800(band 3) / 2600(band 7) / 900(band 8) / 850(band 5), 3G Bands: UMTS 1900 / 2100 / 850 / 900 MHz, 2G Bands: GSM 1800 / 1900 / 850 / 900 MHz, GPRS: Available, EDG...

Front Video Recording

1920x1080 @ 30 fps
1920x1080 @ 30 fps, 1280x720 @ 30 fps

Front Camera Features

HDR
HDR

Front Camera Setup

Single, 32MP
Single, 20MP

Front Camera 1 Resolution

32 MP
20 MP

Front Camera 1 Type

f/2.2 Primary Camera
f/2.2 Primary Camera

Front Camera 1 Lens

2.8" sensor size, 0.8 micrometre pixel size
0.8 micrometre pixel size

Front Aperture

f/2.2
f/2.2

Front Flash

No
-

Weight

172 grams
191 grams

Colors

Prism Crush White, Prism Crush Black, Prism Crush Pink, Prism Crush Blue
Carbon Black, Flame Red, Glacier Blue, Pearl White

Build

Back: Plastic
Back: Gorilla Glass

Dimensions

158.5 x 73.6 x 7.9 mm
156.7 x 74.3 x 8.8 mm

SAR Value

Head: 0.598 W/kg
Head: 1.07 W/kg, Body: 0.723 W/kg

OIS

No
-

Rear Flash

Yes, LED Flash
Yes, Dual LED Flash

Rear Video Recording

3840x2160 @ 30 fps
3840x2160 @ 30 fps, 1920x1080 @ 60 fps, 1280x720 @ 120 fps

Rear Camera Features

8 x Digital Zoom, Auto Flash, Face detection, Touch to focus
Auto Flash, Face detection, Touch to focus

Rear Camera Setup

Quad, 48MP + 12MP + 5MP + 5MP
Triple, 48MP + 13MP + 8MP

Rear Camera 1 Resolution

48 MP
48 MP

Rear Camera 1 Type

f/2.0 (upto 8x Digital Zoom) Primary Camera
f/1.75 Primary Camera

Rear Camera 1 Lens

26 mm focal length, 2.25" sensor size, 0.8 micrometre pixel size
2" sensor size, 0.8 micrometre pixel size

Rear Camera 2 Resolution

12 MP
13 MP

Rear Camera 2 Type

f/2.2, Wide Angle, Ultra-Wide Angle Camera
f/2.4, Wide Angle, Ultra-Wide Angle Camera

Rear Camera 3 Resolution

5 MP
8 MP

Rear Camera 3 Type

f/2.4, Macro Camera
f/2.4 Telephoto (upto 10x Digital Zoom, upto 2x Optical Zoom) Camera

Rear Camera 4 Resolution

5 MP
-

Rear Camera 4 Type

f/2.2, Depth Camera
-

Rear Sensor

ISO-CELL
Exmor-RS CMOS Sensor

Rear Aperture

f/2.0
f/1.75

Rear Camera 2 Lens

-
3" sensor size, 1.12 micrometre pixel size

Rear Camera 3 Lens

-
4.0" sensor size, 1.12 micrometre pixel size

Fingerprint Scanner

Yes
Yes

Fingerprint Scanner Position

On-Screen
On-Screen

Fingerprint Scanner Type

Optical
Optical

Face Unlock

Yes
Yes
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