Samsung Galaxy A51 vs Samsung Galaxy S21 Specs Comparison

Availability

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

Design

Dimensions
6.24 x 2.90 x 0.31 inches 158.5 x 73.6 x 7.9 mm	5.97 x 2.80 x 0.31 inches 151.7 x 71.2 x 7.9 mm
Weight
6.07 oz / 172.0 g	6.03 oz / 171.0 g
Materials
Back: Plastic Frame: Plastic	Back: Plastic Frame: Aluminum
Resistance
	Water, Dust; IP68
Biometrics
2D Face unlock, Optical in-screen fingerprint	2D Face unlock, Ultrasonic in-screen fingerprint
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	Phantom pink, Violet, Gray, White

Display

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

PhoneArena Display Test

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

Learn more on our PhoneArena Display Test Results page.

Hardware

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

Battery

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

PhoneArena Battery Tests

Battery Life Estimate

5h 22min

Browsing

11h 35min

Video

8h 35min

Gaming

6h 40min

Battery Life Estimate

4h 28min

Browsing

7h 47min

Video

7h 36min

Gaming

7h 9min

Learn more on our PhoneArena Battery Test Results page

Camera

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

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	a,b,g,n,ac,Wi-Fi 6,dual-band MIMO, Wi-Fi Direct, Hotspot 802.11 a, b, g, n, ac, ax
USB
Type-C, USB 2.0	Type-C, USB 3.2
Sensors
Accelerometer, Gyroscope, Compass, Hall (for flip covers), Ambient light sensor, Proximity sensor	Accelerometer, Gyroscope, Compass, Hall (for flip covers), Barometer, 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+

Multimedia

Headphones
3.5mm jack	No 3.5mm jack
Speakers
Earpiece, Loudspeaker	Earpiece, Multiple speakers
Features
Dolby Atmos	32-Bit DAC, Dolby Atmos, aptX, Dolby Digital, Dolby Digital Plus
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, 20, 25, 26, 28, 29, 30, 66, 71	1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 18, 19, 20, 25, 26, 28, 30, 66, 71
4G (TDD) Bands
38, 39, 41	38, 39, 40, 41, 46, 48
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, UMTS
SIM type
Nano SIM	Nano SIM

Regulatory Approval

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

Alternative variants

with 128GB storage

Memory	6GB/128GB

with 256GB storage

Memory	256GB

for Verizon

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

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 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	Samsung Galaxy S21 Specs
PhoneArena Review
Samsung Galaxy A51 Review	Samsung Galaxy S21 Review
User Reviews
Samsung Galaxy A51 User Reviews	Samsung Galaxy S21 User Reviews