Samsung Galaxy J7 vs LG K51 vs Samsung Galaxy A21

Compare phone and tablet specifications of up to three devices at once.

Comparison mode:

Display

Size:

5.5 inches
6.5 inches
6.5 inches

Resolution:

1280 x 720 pixels, 267 PPI
1560 x 720 pixels, 19.5:9 ratio, 264 PPI
1600 x 720 pixels, 20:9 ratio, 270 PPI

Technology:

Super AMOLED
IPS LCD
IPS LCD

Screen-to-body:

69.72 %
79.70 %
79.20 %

Colors:

16 777 216

Touchscreen:

Capacitive, Multi-touch

Features:

Ambient light sensor, Proximity sensor
Ambient light sensor, Proximity sensor
60Hz refresh rate, Ambient light sensor, Proximity sensor

Hardware

System chip:

Qualcomm Snapdragon 615 8939
MediaTek Helio P22 MT6762
Mediatek Helio P35

Processor:

Octa-core, 1500 MHz, ARM Cortex-A53, 64-bit
Octa-core, 2000 MHz, Arm Cortex-A53, 64-bit, 12 nm
Octa-core, 2300 MHz, Arm Cortex-A53, 64-bit, 12 nm

GPU:

Adreno 405
IMG PowerVR GE8320
PowerVR GE8320

RAM:

1.5GB LPDDR3
3GB
3GB LPDDR4

Internal storage:

16GB, available to use: 11.6 GB
32GB, available to use: 18 GB
32GB (eMMC 5.1), available to use: 19.8 GB

Storage expansion:

microSDXC up to 128 GB
microSDXC up to 2000 GB
microSDXC up to 512 GB

Device type:

Smartphone
Smartphone
Smartphone

OS:

Android (6.0 Marshmallow, 5.1 Lollipop)
Android (10)
Android (10), Samsung One UI

Battery

Capacity:

3000 mAh
4000 mAh
4000 mAh

Type:

User replaceable
Li - Ion, Not user replaceable
Li - Polymer, Not user replaceable

Charging:

Fast charging

Max charge speed:

Wired: 15.0W

Camera

Rear:

Single camera
Triple camera
Quad camera

Main camera:

13 MP (Autofocus)
13 MP (PDAF)
16 MP (PDAF)

Specifications:

Aperture size: F1.9; Focal length: 28 mm
Aperture size: F1.8; Sensor size: 1/3"; Pixel size: 1.12 μm
Aperture size: F1.8; Sensor size: 1/3.06"; Pixel size: 1 μm

Second camera:

5 MP (Ultra-wide)
8 MP (Ultra-wide)

Specifications:

Aperture size: F2.2; Sensor size: 1/5"; Pixel size: 1.12 μm
Aperture size: F2.2; Sensor size: 1/4"; Pixel size: 1.12 μm

Third camera:

2 MP (Depth information)
2 MP (Macro)

Specifications:

Sensor size: 1/5"; Pixel size: 1.75 μm
Aperture size: F2.4

Fourth camera:

2 MP (Depth information)

Specifications:

Aperture size: F2.4

Video recording:

1920x1080 (Full HD) (30 fps)
1920x1080 (Full HD)
1920x1080 (Full HD) (30 fps)

Features:

Video calling
Picture-taking during video recording

Front:

5 MP (Flash)
13 MP
13 MP

Video capture:

1920x1080 (Full HD)
1920x1080 (Full HD)

Design

Dimensions:

6.00 x 3.09 x 0.30 inches (152.4 x 78.6 x 7.5 mm)
6.57 x 3.07 x 0.33 inches (166.9 x 77.9 x 8.4 mm)
6.61 x 3.02 x 0.32 inches (167.8 x 76.7 x 8.1 mm)

Weight:

6.03 oz (171.0 g)
7.17 oz (203.4 g)
6.81 oz (193.0 g)

Materials:

Back: Plastic; Frame: Plastic

Resistance:

Yes; MIL-STD-810 certified

Biometrics:

Fingerprint (touch)
Fingerprint (touch)

Features:

Touch sensitive control keys

Keys:

Left: Volume control; Right: Lock/Unlock key
Left: Volume control; Right: Lock/Unlock key
Right: Volume control, Lock/Unlock key

Colors:

Black, Gold, White
Titan gray
Black

Cellular

LTE (FDD):

Bands 1(2100), 3(1800), 5(850), 7(2600), 8(900), 20(800 DD)
Bands 2(1900), 3(1800), 4(AWS-1), 5(850), 7(2600), 12(700 a), 13(700 c), 20(800 DD), 25(1900+), 26(850+), 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)

LTE (TDD):

Bands 40(2300)
Bands 41(2600+)
Bands 38(2600), 39(1900+), 40(2300), 41(2600+)

UMTS:

Bands 5(850), 8(900), 2(1900), 1(2100)
Bands 1(2100), 2(1900), 4(1700/2100), 5(850), 8(900)
Bands 5(850), 8(900), 4(1700/2100), 2(1900), 1(2100)

Data Speed:

LTE, HSPA
LTE-A Cat 6 (300/50 Mbit/s), 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

Dual SIM:

Yes

SIM type:

Micro SIM
Nano SIM
Nano SIM

HD Voice:

Yes
Yes

VoLTE:

Yes

Multimedia

Headphones:

3.5mm jack
3.5mm jack
3.5mm jack

Speakers:

Earpiece, Loudspeaker
Earpiece, Multiple speakers
Earpiece, Loudspeaker

Features:

Album art cover, Background playback
DTS:X Virtual Surround

Screen mirroring:

Wireless screen share
Wireless screen share
Wireless screen share

Radio:

FM, RDS
FM
FM

Additional microphone(s):

for Noise cancellation

Connectivity & Features

Bluetooth:

4.1
5.0
5.0

Wi-Fi:

802.11 b, g, n; Hotspot, Wi-Fi Direct
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:

microUSB, USB 2.0
Type-C (reversible), USB 2.0
Type-C (reversible), USB 2.0

Features:

Mass storage device, Charging
Charging
Charging

Location:

GPS, A-GPS, Glonass
GPS, A-GPS, Cell ID, Wi-Fi positioning
GPS, A-GPS, Glonass, BeiDou, Cell ID, Wi-Fi positioning

Sensors:

Accelerometer, Hall (for flip covers)
Accelerometer, Gyroscope, Compass
Accelerometer, Gyroscope, Compass

Other:

ANT+
NFC

Hearing aid compatible:

M3, T3
M4, T3

Phone features

Notifications:

Haptic feedback, Music ringtones (MP3), Polyphonic ringtones, Vibration, Flight mode, Silent mode, Speakerphone

Other features:

Voice dialing, Voice commands, Voice recording

Regulatory Approval

FCC approval:

Date approved:

Jun 16, 2020
Apr 17, 2020

FCC ID value:

ZNFL555DL
ZCASMA215U

Measured SAR:

Head:

0.66 W/kg
0.42 W/kg

Body:

1.20 W/kg
1.27 W/kg

Simultaneous Transmission:

1.59 W/kg
1.27 W/kg

Wireless Router:

1.27 W/kg
1.27 W/kg

Phablet:

3.96 W/kg

Buyers information

Price:

$ 234
$ 200
$ 250

User Manual:

This is the official LG K51 User Guide in English provided from the manufacturer.

In The Box:

Charger, USB Cable, SIM Ejector
This is the official Samsu​ng Galaxy A21 User Guide in English provided from the manufacturer.

Availability

Officially announced:

Jul 16, 2015
May 06, 2020
Apr 08, 2020
FCC OKs Cingular\'s purchase of AT&T Wireless