Samsung Galaxy A51 vs Samsung Galaxy S21 Ultra 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	9.1
Samsung Galaxy A51	Samsung Galaxy S21 Ultra
Released · Dec 27, 2019	Released · Jan 29, 2021
6.5-inch · 2400x1080px	6.8-inch · 3200x1440px
Quad camera	Quad camera
4GB · 128GB	12GB · 128GB
4000 mAh	5000 mAh
Check prices	Check prices

Design

Dimensions
6.24 x 2.90 x 0.31 inches 158.5 x 73.6 x 7.9 mm	6.50 x 2.98 x 0.35 inches (~0.37 inches with camera bump) 165.1 x 75.6 x 8.9 mm (~9.4 mm with camera bump)
Weight
6.07 oz (172.0 g)	8.04 oz (229.0 g)
Materials
Back: Plastic Frame: Plastic	Back: Glass (Corning Gorilla Glass Victus) 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 black, Silver

Display

Size
6.5-inch	6.8-inch
Resolution
2400x1080px, 20:9 ratio, 405 PPI	3200x1440px, 20:9 ratio, 516 PPI
Technology
Super AMOLED	Dynamic AMOLED
Refresh rate
60Hz	120Hz (adaptable)
Screen-to-body
87.37 %	89.33 %
Peak brightness
	1500 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 SM8350 (5 nm)
Processor
Octa-core 2300 MHz 4x 2.3GHz Cortex-A73 + 4x 1.7GHz Cortex-A53	Octa-core 1x 2.84GHz Kryo 680 + 3x 2.42GHz Kryo 680 + 4x 1.80GHz Kryo 680
GPU
Mali-G72 MP3	Adreno 660
Memory
4GB (LPDDR4)/128GB	12GB (LPDDR5)/128GB (UFS 3.1)
Storage expansion
microSDXC up to 512 GB	not expandable
OS
Android (11, 10)	Android (14, 13, 12, 11)

Battery

Type
4000 mAh, Li - Polymer	5000 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

Battery Life Estimate

5h 22min

Browsing

11h 35min

Video

8h 35min

Gaming

6h 40min

Battery Life Estimate

6h 15min

Browsing

14h 43min

Video

8h 52min

Gaming

8h 40min

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	108 MP (OIS, Laser and PDAF) Aperture size: F1.8 Focal length: 24 mm Sensor size: 1/1.33" Pixel size: 0.8 μm
Second camera
12 MP (Ultra-wide) Aperture size: F2.2 Focal Length: 13 mm Pixel size: 1.12 μm	12 MP (Ultra-wide, PDAF) 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	10 MP (Telephoto, OIS, PDAF) Optical zoom: 3.0x Aperture size: F2.4 Focal Length: 70 mm Sensor size: 1/3.2" Pixel size: 1.22 μm
Fourth camera
5 MP (Depth information) Aperture size: F2.2 Sensor size: 1/5" Pixel size: 1.12 μm	10 MP (Telephoto, Periscope, OIS, PDAF) Optical zoom: 3.0x Aperture size: F2.4 Focal Length: 70 mm Sensor size: 1/3.2" Pixel size: 1.22 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, Video light, EIS
Front
32 MP (HDR) Video capture: 1080p	40 MP (PDAF, HDR) Video capture: 4K UHD (60 fps)

Connectivity & Features

Bluetooth
5.0	5.1
WLAN
a,b,g,n,ac,dual-band Wi-Fi Direct, Hotspot	a,b,g,n,ac,Wi-Fi 6,dual-band MIMO, Wi-Fi Direct, Hotspot
USB
Type-C, USB 2.0	Type-C, USB 3.2
Sensors
Accelerometer, Gyroscope, Compass, Hall (for flip covers)	Accelerometer, Gyroscope, Compass, Hall (for flip covers), Barometer
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	Wireless screen share
Radio
FM	FM, Stereo, RDS
Additional microphone(s)
Noise cancellation	Noise cancellation, Video recording

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(700 d), 30(2300 WCS), 66(AWS-3), 71(600)	Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 18, 19, 20, 25, 26, 28, 30(2300 WCS), 66(AWS-3), 71(600)
4G (TDD)
Bands 38, 39, 41	Bands 38, 39, 40, 41, 46, 48
3G
Bands 1, 2, 4, 5, 8	Bands 1, 2, 4, 5, 8
Data Speed
LTE-A, HSDPA+ (4G) 42.2 Mbit/s, HSUPA 5.76 Mbit/s	LTE-A Pro Cat 20 (2000/150 Mbit/s)
SIM type
Nano SIM	Nano SIM

Regulatory Approval

FCC approval
Date approved: Nov 28, 2019 FCC ID value: A3LSMA515FN	Date approved: Dec 22, 2020 FCC ID value: A3LSMG998U
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: 0.77 W/kg Body: 1.02 W/kg Simultaneous Transmission: 1.59 W/kg Wireless Router: 1.16 W/kg Phablet: 3.15 W/kg

Buyers information

MSRP
$ 400	$ 1200 / € 1399

Availability

Officially announced
Dec 12, 2019	Jan 14, 2021

Alternative variants

with 128GB storage


Memory	6GB/128GB

with 256GB storage


Memory	256GB
Colors	Phantom black
MSRP	$ 1250

for Verizon


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

with 512GB storage


Memory	16GB/512GB
Colors	Phantom black
MSRP	$ 1380

for AT&T


4G (FDD)	Bands 2, 4, 5, 12, 13, 25, 26, 66(AWS-3), 71(600)
4G (TDD)	Bands 41

for Europe


System chip	Samsung Exynos 2100 (5 nm)
Processor	Octa-core 1x 2.91GHz Cortex-X1 + 3x 2.81GHz Cortex-A78 + 4x 2.2GHz Cortex-A55
GPU	Mali G78 MP14
Weight	8.01 oz (227.0 g)
5G	Bands SA, NSA, Sub-6
FCC approval	Date approved: Dec 22, 2020 FCC ID value: A3LSMG998B
Measured SAR	Head: 0.16 W/kg Body: 0.72 W/kg Simultaneous Transmission: 1.59 W/kg Wireless Router: 1.34 W/kg Phablet: 3.86 W/kg

for Sprint


4G (FDD)	Bands 2, 4, 5, 12, 13, 25, 26, 66(AWS-3), 71(600)
4G (TDD)	Bands 41

for Europe


4G (FDD)	Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 20, 26, 28, 66(AWS-3)
4G (TDD)	Bands 38, 40, 41
Dual SIM	Yes

Links

Full specifications
Samsung Galaxy A51 Specs	Samsung Galaxy S21 Ultra Specs
PhoneArena Review
Samsung Galaxy A51 Review	Samsung Galaxy S21 Ultra Review
User Reviews
Samsung Galaxy A51 User Reviews	Samsung Galaxy S21 Ultra User Reviews