Samsung Galaxy A51 vs Samsung Galaxy S21 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	8.5
Samsung Galaxy A51	Samsung Galaxy S21
Released · Dec 27, 2019	Released · Jan 29, 2021
6.5-inch · 2400 x 1080 px	6.2-inch · 2400 x 1080 px
48 MP Main · 32 MP Selfie	12 MP Main · 10 MP Selfie
4GB · 128GB	8GB · 128GB
4000 mAh	4000 mAh
Check prices	Check prices

Display

Size
6.5-inch	6.2-inch
Resolution
2400 x 1080 px, 20:9 ratio, 405 PPI	2400 x 1080 px, 20:9 ratio, 424 PPI
Technology
Super AMOLED	Dynamic AMOLED
Refresh rate
60Hz	120Hz (adaptive)
Screen-to-body
87.37 %	86.06 %
Peak brightness
	1300 cd/m2 (nit)
Features
Scratch-resistant glass (Corning Gorilla Glass 3), Ambient light sensor, Proximity sensor	HDR support, Scratch-resistant glass (Corning Gorilla Glass Victus), Ambient light sensor, Proximity sensor

Hardware

System chip
Samsung Exynos 9611 (10 nm)	Qualcomm Snapdragon 888 (5 nm)
Processor
Octa-core, 2300 MHz, 4x 2.3GHz Cortex-A73 + 4x 1.7GHz Cortex-A53, 64-bit	Octa-core, 1x 2.84GHz Kryo 680 + 3x 2.42GHz Kryo 680 + 4x 1.80GHz Kryo 680, 64-bit
GPU
Mali-G72 MP3	Adreno 660
RAM
4GB (LPDDR4)	8GB (LPDDR5)
Internal storage
128GB, available to use: 105.9 GB	128GB (UFS 3.0), not expandable
Storage expansion
microSDXC up to 512 GB
OS
Android (11, 10), Samsung One UI	Android (13, 12, 11), Samsung One UI
Device type
Smartphone	Smartphone

Battery

Capacity
4000 mAh	4000 mAh
Type
Li - Polymer, Not user replaceable	Li - Polymer, Not user replaceable
Charging
Fast charging	Qualcomm Quick Charge 2.0, USB Power Delivery, Samsung Adaptive Fast Charging, Qi and Powermat wireless charging, Reverse wireless charging
Max charge speed
	Wired: 25.0W Wireless: 15.0W

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

Camera

Rear
Quad camera	Triple camera
Main camera
48 MP (PDAF) Specifications: Aperture size: F2.0 Focal length: 26 mm Sensor size: 1/2" Pixel size: 0.8 μm	12 MP (OIS, PDAF) Specifications: Aperture size: F1.8 Focal length: 26 mm Sensor size: 1/1.76" Pixel size: 1.8 μm
Second camera
12 MP (Ultra-wide) Specifications: Aperture size: F2.2 Focal Length: 13 mm Pixel size: 1.12 μm	64 MP (Telephoto, OIS, PDAF) Specifications: Aperture size: F2.0 Focal Length: 29 mm Sensor size: 1/1.7" Pixel size: 0.8 μm
Third camera
5 MP (Macro) Specifications: Aperture size: F2.4 Focal Length: 40 mm	12 MP (Ultra-wide, Autofocus) Specifications: Aperture size: F2.2 Focal Length: 13 mm Sensor size: 1/2.55" Pixel size: 1.4 μm
Fourth camera
5 MP (Depth information) Specifications: Aperture size: F2.2 Sensor size: 1/5" Pixel size: 1.12 μm
Flash
LED	LED
Video recording
3840x2160 (4K UHD) (30 fps), 1920x1080 (Full HD) (120 fps), 1280x720 (HD) (240 fps) Features: Hyperlapse, EIS	7680x4320 (8K UHD) (24 fps), 3840x2160 (4K UHD) (60 fps), 1920x1080 (Full HD) (240 fps), 1280x720 (HD) (960 fps) Features: OIS, HDR, Hyperlapse, Continuous autofocus, Video light, EIS
Front
32 MP (HDR), Video capture: 1920x1080 (Full HD)	10 MP (PDAF, HDR), Video capture: 3840x2160 (4K UHD) (60 fps)

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

Cellular

5G
	Bands n2, n5, n12, n25, n41, n66, n71, n77, n260, n261, SA, NSA, Sub-6, mmWave
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), 14(700 PS), 18(800 Lower), 19(800 Upper), 20(800 DD), 25(1900+), 26(850+), 28(700 APT), 30(2300 WCS), 66(AWS-3), 71(600)
4G (TDD)
Bands 38(2600), 39(1900+), 41(2600+)	Bands 38(2600), 39(1900+), 40(2300), 41(2600+), 46, 48(3600)
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, HSDPA+ (4G) 42.2 Mbit/s, HSUPA 5.76 Mbit/s, UMTS
SIM type
Nano SIM	Nano SIM

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	Wireless screen share
Radio
FM	FM, Stereo, RDS
Additional microphone(s)
Noise cancellation	Noise cancellation, Video recording

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,ax(Wi-Fi 6),dual-band MIMO, Wi-Fi Direct, Hotspot
USB
Type-C (reversible), USB 2.0, Features: Charging, OTG	Type-C (reversible), USB 3.2, Features: Charging, Headphones port, OTG, Video out
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
Sensors
Accelerometer, Gyroscope, Compass, Hall (for flip covers)	Accelerometer, Gyroscope, Compass, Hall (for flip covers), Barometer
Other
NFC, ANT+	NFC, ANT+

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

Buyers information

MSRP
$ 400	$ 800
In The Box
	C to C Data Cable, Ejection Pin

Availability

Officially announced
Dec 12, 2019	Jan 14, 2021

Alternative variants

with 128GB storage


RAM	6GB
Internal storage	128GB

with 256GB storage


Internal storage	256GB

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 Europe


System chip	Samsung Exynos 2100 (5 nm)
Processor	Octa-core, 2900 MHz, 1x 2.91GHz Cortex-X1 + 3x 2.81GHz Cortex-A78 + 4x 2.2GHz Cortex-A55, 64-bit
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(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

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