Samsung Galaxy A51 vs Samsung Galaxy A21 Specs Comparison

Compare mobile phone specifications of up to three devices at once. Our specs comparison tool helps you find and compare the perfect phone for your needs.

7.0
Samsung Galaxy A51
Samsung Galaxy A51 Samsung Galaxy A21
Released · Dec 27, 2019
Released · Jun 29, 2020
6.5-inch · 2400x1080px
6.5-inch · 1600x720px
48 MP Main · 32 MP Selfie
16 MP Main · 13 MP Selfie
4GB · 128GB
3GB · 32GB
4000 mAh
4000 mAh
Check prices Check prices

Display

Size
6.5-inch 6.5-inch
Resolution
2400x1080px, 20:9 ratio, 405 PPI 1600x720px, 20:9 ratio, 270 PPI
Technology
Super AMOLED IPS LCD
Refresh rate
60Hz 60Hz
Screen-to-body
87.37 % 79.20 %
Features
Scratch-resistant glass (Corning Gorilla Glass 3), Ambient light sensor, Proximity sensor Ambient light sensor, Proximity sensor

Hardware

System chip
Samsung Exynos 9611 (10 nm) Mediatek Helio P35 MT6765 (12 nm)
Processor
Octa-core
2300 MHz
4x 2.3GHz Cortex-A73 + 4x 1.7GHz Cortex-A53
64-bit
Octa-core
4x 2.3GHz Cortex-A53 + 4x 1.8GHz Cortex-A53
64-bit
GPU
Mali-G72 MP3 PowerVR GE8320
RAM
4GB (LPDDR4) 3GB (LPDDR4)
Internal storage
128GB, available to use: 105.9 GB 32GB (eMMC 5.1), available to use: 19.8 GB
Storage expansion
microSDXC up to 512 GB microSDXC up to 512 GB
OS
Android (11, 10), Samsung One UI Android (10), Samsung One UI

Battery

Capacity
4000 mAh 4000 mAh
Type
Li - Polymer, Not user replaceable Li - Polymer, Not user replaceable
Charging
Fast charging Fast charging
Max charge speed
Wired: 15.0W
PhoneArena Battery Tests
Battery Life Estimate
5h 22min
Browsing
11h 35min
Video
8h 35min
Gaming
6h 40min
Battery Life Estimate
Untested
Browsing
Untested
Video
Untested
Gaming
Untested

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
16 MP (PDAF)
Aperture size: F1.8
Sensor size: 1/3.06"
Pixel size: 1 μm
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
Sensor size: 1/4"
Pixel size: 1.12 μm
Third camera
5 MP (Macro)
Aperture size: F2.4
Focal Length: 40 mm
2 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)
Aperture size: F2.4
Flash
LED LED
Video recording
3840x2160 (4K UHD) (30 fps), 1920x1080 (Full HD) (120 fps), 1280x720 (HD) (240 fps)
Hyperlapse, EIS
1920x1080 (Full HD) (30 fps)
Front
32 MP (HDR), Video capture: 1920x1080 (Full HD) 13 MP, Video capture: 1920x1080 (Full HD)

Design

Dimensions
6.24 x 2.90 x 0.31 inches
(158.5 x 73.6 x 7.9 mm)
6.61 x 3.02 x 0.32 inches
(167.8 x 76.7 x 8.1 mm)
Weight
6.07 oz(172.0 g) 6.81 oz(193.0 g)
Materials
Back: Plastic
Frame: Plastic
Back: Plastic
Frame: Plastic
Biometrics
2D Face unlock, Optical in-screen fingerprint 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 Black

Cellular

4G (FDD)
Bands 1(2100), 2(1900), 3(1800), 4(AWS-1), 5(850), 7(2600), 8(900), 12(700 a), 13(700 c), 14(700 PS), 20(800 DD), 25(1900+), 26(850+), 28(700 APT), 29(700 d), 30(2300 WCS), 66(AWS-3), 71(600) Bands 1(2100), 2(1900), 3(1800), 4(AWS-1), 5(850), 7(2600), 8(900), 12(700 a), 13(700 c), 17(700 b), 20(800 DD), 25(1900+), 26(850+), 28(700 APT), 66(AWS-3), 71(600)
4G (TDD)
Bands 38(2600), 39(1900+), 41(2600+) Bands 38(2600), 39(1900+), 40(2300), 41(2600+)
3G
Bands 1(2100), 2(1900), 4(1700/2100), 5(850), 8(900) Bands 1(2100), 2(1900), 4(1700/2100), 5(850), 8(900)
Data Speed
LTE-A, HSDPA+ (4G) 42.2 Mbit/s, HSUPA 5.76 Mbit/s LTE-A Cat 6 (300/50 Mbit/s), HSDPA+ (4G) 42.2 Mbit/s, HSUPA 5.76 Mbit/s
SIM type
Nano SIM Nano SIM
HD Voice
Yes

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

Connectivity & Features

Bluetooth
5.0 5.0
Wi-Fi
802.11 a,b,g,n,ac,dual-band
Wi-Fi Direct, Hotspot
802.11 a,b,g,n,ac,dual-band
Wi-Fi Direct, Hotspot
USB
Type-C (reversible), USB 2.0, Features: Charging, OTG Type-C (reversible), USB 2.0, Features: Charging
Hearing aid compatible
M4/T3
Location
GPS, A-GPS, Glonass, Galileo, BeiDou, Cell ID, Wi-Fi positioning GPS, A-GPS, Glonass, BeiDou, Cell ID, Wi-Fi positioning
Sensors
Accelerometer, Gyroscope, Compass, Hall (for flip covers) Accelerometer, Gyroscope, Compass
Other
NFC, ANT+ NFC

Regulatory Approval

FCC approval
Date approved: Nov 28, 2019
FCC ID value: A3LSMA515FN
Date approved: Apr 17, 2020
FCC ID value: ZCASMA215U
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
Head: 0.42 W/kg
Body: 1.27 W/kg
Simultaneous Transmission: 1.27 W/kg
Wireless Router: 1.27 W/kg

Buyers information

MSRP
$ 400 $ 250
In The Box
This is the official Samsu​ng Galaxy A21 User Guide in English provided from the manufacturer.

Availability

Officially announced
Dec 12, 2019 Apr 08, 2020

Alternative variants

with 128GB storage
RAM 6GB
Internal storage 128GB
for Verizon
4G (FDD) Bands 1(2100), 2(1900), 3(1800), 5(850), 7(2600), 8(900), 20(800 DD), 28(700 APT)
4G (TDD) Bands 38(2600), 40(2300), 41(2600+)
3G Bands 5(850), 8(900), 2(1900), 1(2100)
for Verizon
4G (FDD) Bands 2(1900), 3(1800), 4(AWS-1), 5(850), 7(2600), 13(700 c), 20(800 DD), 28(700 APT), 66(AWS-3)
3G Bands 5(850), 8(900), 2(1900), 1(2100)
for Sprint
4G (FDD) Bands 2(1900), 3(1800), 4(AWS-1), 5(850), 7(2600), 12(700 a), 13(700 c), 25(1900+), 26(850+), 66(AWS-3), 71(600)
4G (TDD) Bands 41(2600+)
for AT&T
4G (FDD) Bands 2(1900), 4(AWS-1), 5(850), 12(700 a), 13(700 c), 25(1900+), 26(850+), 66(AWS-3), 71(600)
4G (TDD) Bands 41(2600+)
for Sprint
4G (FDD) Bands 2(1900), 4(AWS-1), 5(850), 12(700 a), 13(700 c), 25(1900+), 26(850+), 66(AWS-3), 71(600)
4G (TDD) Bands 41(2600+)
for Europe
4G (FDD) Bands 1(2100), 2(1900), 3(1800), 4(AWS-1), 5(850), 7(2600), 8(900), 12(700 a), 13(700 c), 17(700 b), 20(800 DD), 26(850+), 28(700 APT), 66(AWS-3)
4G (TDD) Bands 38(2600), 40(2300), 41(2600+)
Dual SIM Yes
FCC OKs Cingular\'s purchase of AT&T Wireless