Samsung Galaxy S21 vs Samsung Galaxy A51 Specs Comparison

Availability

Officially announced
Jan 14, 2021	Dec 12, 2019
Prices (MSRP)
$800	$400

Design

Dimensions
5.97 x 2.80 x 0.31 inches 151.7 x 71.2 x 7.9 mm	6.24 x 2.90 x 0.31 inches 158.5 x 73.6 x 7.9 mm
Weight
6.03 oz / 171.0 g	6.07 oz / 172.0 g
Materials
Back: Plastic Frame: Aluminum	Back: Plastic Frame: Plastic
Resistance
Water, Dust; IP68
Biometrics
2D Face unlock, Ultrasonic in-screen fingerprint	2D Face unlock, Optical in-screen fingerprint
Keys
Right: Volume control, Lock/Unlock key	Right: Volume control, Lock/Unlock key
Colors
Phantom pink, Violet, Gray, White	Prism Crush black, Prism Crush white, Prism Crush pink, Prism Crush blue

Display

Size
6.2-inch, 86.06% screen-to-body	6.5-inch, 87.37% screen-to-body
Type
Dynamic AMOLED, 120Hz, HDR, 1300 nits	Super AMOLED, 60Hz
Resolution
2400x1080px, 20:9 ratio, 424 PPI	2400x1080px, 20:9 ratio, 405 PPI
Protection
Corning Gorilla Glass Victus	Corning Gorilla Glass 3

PhoneArena Display Test

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

Learn more on our PhoneArena Display Test Results page.

Hardware

System chip
Snapdragon 888 (5 nm)	Samsung Exynos 9611 (10 nm)
Processor
Octa-core 1x2.84GHz Kryo 680 3x2.42GHz Kryo 680 4x1.80GHz Kryo 680	Octa-core 2300 MHz 4x2.3GHz Cortex-A73 4x1.7G​Hz Cortex-A53
GPU
Adreno 660	Mali-G72 MP3
Memory
8GB (LPDDR5)/128GB (UFS 3.0) 8GB/256GB	4GB (LPDDR4)/128GB 6GB/128GB
Storage expansion
not expandable	microSDXC up to 512 GB
OS
Android (13, 12, 11)	Android (11, 10)

Battery

Type
4000 mAh, Li - Polymer	4000 mAh, Li - Polymer
Charging
Qualcomm Quick Charge 2.0, USB Power Delivery, Samsung Adaptive Fast Charging Qi and Powermat wireless charging, Reverse wireless charging	Fast charging
Charge speed
Wired: 25.0W Wireless: 15.0W

PhoneArena Battery Tests

Battery Life Estimate

4h 28min

Browsing

7h 47min

Video

7h 36min

Gaming

7h 9min

Battery Life Estimate

5h 22min

Browsing

11h 35min

Video

8h 35min

Gaming

6h 40min

Learn more on our PhoneArena Battery Test Results page

Camera

Rear
Triple camera	Quad camera
Main camera
12 MP (OIS, PDAF) Aperture size: F1.8 Focal length: 26 mm Sensor size: 1/1.76" Pixel size: 1.8 μm	48 MP (PDAF) Aperture size: F2.0 Focal length: 26 mm Sensor size: 1/2" Pixel size: 0.8 μm
Second camera
12 MP (Ultra-wide, Autofocus) Aperture size: F2.2 Focal Length: 13 mm Sensor size: 1/2.55" Pixel size: 1.4 μm	12 MP (Ultra-wide) Aperture size: F2.2 Focal Length: 13 mm Pixel size: 1.12 μm
Third camera
64 MP (Telephoto, OIS, PDAF) Aperture size: F2.0 Focal Length: 29 mm Sensor size: 1/1.7" Pixel size: 0.8 μm	5 MP (Macro) Aperture size: F2.4 Focal Length: 40 mm
Fourth camera
	5 MP (Depth information) Aperture size: F2.2 Sensor size: 1/5" Pixel size: 1.12 μm
Flash
LED	LED
Video recording
8K UHD (24 fps), 4K UHD (60 fps), 1080p (240 fps), 720p (960 fps) OIS, HDR, Hyperlapse, Continuous autofocus, Video light, EIS	4K UHD (30 fps), 1080p (120 fps), 720p (240 fps) Hyperlapse, EIS
Front
10 MP (PDAF, HDR) Video capture: 4K UHD (60 fps)	32 MP (HDR) Video capture: 1080p

Connectivity & Features

Bluetooth
5.0	5.0
WLAN
a,b,g,n,ac,Wi-Fi 6,dual-band MIMO, Wi-Fi Direct, Hotspot 802.11 a, b, g, n, ac, ax	a,b,g,n,ac,dual-band Wi-Fi Direct, Hotspot 802.11 a, b, g, n, ac
USB
Type-C, USB 3.2	Type-C, USB 2.0
Sensors
Accelerometer, Gyroscope, Compass, Hall (for flip covers), Barometer, Ambient light sensor, Proximity sensor	Accelerometer, Gyroscope, Compass, Hall (for flip covers), Ambient light sensor, Proximity sensor
Hearing aid compatible
M3/T3
Location
GPS, A-GPS, Glonass, Galileo, BeiDou, Cell ID, Wi-Fi positioning	GPS, A-GPS, Glonass, Galileo, BeiDou, Cell ID, Wi-Fi positioning
Other
NFC, ANT+	NFC, ANT+

Discover more

Full Specs Samsung Galaxy S21 Specs PA Review Samsung Galaxy S21 Review

Full Specs Samsung Galaxy A51 Specs PA Review Samsung Galaxy A51 Review

Multimedia

Headphones
No 3.5mm jack	3.5mm jack
Speakers
Earpiece, Multiple speakers	Earpiece, Loudspeaker
Features
32-Bit DAC, Dolby Atmos, aptX, Dolby Digital, Dolby Digital Plus	Dolby Atmos
Screen mirroring
	Wireless screen share
Radio
	FM
Additional microphone(s)
	Noise cancellation

Cellular

5G Bands
n2, n5, n12, n25, n41, n66, n71, n77, n260, n261, SA, NSA, Sub-6, mmWave
4G (FDD) Bands
1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 18, 19, 20, 25, 26, 28, 30, 66, 71	1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 20, 25, 26, 28, 29, 30, 66, 71
4G (TDD) Bands
38, 39, 40, 41, 46, 48	38, 39, 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, UMTS	LTE-A, HSDPA+ (4G) 42.2 Mbit/s, HSUPA 5.76 Mbit/s
SIM type
Nano SIM	Nano SIM

Regulatory Approval

FCC approval
Date approved: Dec 08, 2020 FCC ID value: A3LSMG991U	Date approved: Nov 28, 2019 FCC ID value: A3LSMA515FN
Measured SAR
Head: 0.36 W/kg Body: 1.08 W/kg Simultaneous Transmission: 3.96 W/kg Wireless Router: 1.09 W/kg Phablet: 2.49 W/kg	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 256GB storage

Memory	256GB

with 128GB storage

Memory	6GB/128GB

for Europe

System chip	Samsung Exynos 2100 (5 nm)
Processor	Octa-core 2900 MHz 1x2.91GHz Cortex-X1 3x2.81G​Hz Cortex-A78 4x2.2G​Hz Cortex-A55
GPU	Mali G78 MP14
Weight	5.96 oz / 169.0 g
5G Bands	SA, NSA, Sub-6
FCC approval	Date approved: Dec 18, 2020 FCC ID value: A3LSMG991B
Measured SAR	Head: 0.42 W/kg Body: 0.94 W/kg Simultaneous Transmission: 3.96 W/kg Wireless Router: 1.34 W/kg Phablet: 2.37 W/kg

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