Apple Watch Series 2 (38mm) vs Apple Watch Series 4 (40mm) 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.

Apple Watch Series 2 (38mm) Apple Watch Series 4 (40mm)
Released · September 2016
Released · September 2018
1.5-inch · 340x272px
1.6-inch · 394x324px
0.5GB · 8GB
1GB · 16GB
273 mAh
225 mAh
Check prices Check prices

Design

Dimensions
1.52 x 1.31 x 0.45 inches
38.6 x 33.3 x 11.4 mm
1.57 x 1.34 x 0.42 inches
40.0 x 34.0 x 10.7 mm
Weight
1.48 oz (41.9 g) 1.06 oz (30.1 g)
Materials
Frame: Stainless steel Frame: Aluminum
Resistance
Water Water
Colors
Silver, Black Silver, Black

Display

Size
1.5-inch 1.6-inch
Resolution
340x272px, 290 PPI 394x324px, 325 PPI
Technology
OLED OLED
Screen-to-body
55.12 % 57.48 %
Peak brightness
1000 cd/m2 (nit) 1000 cd/m2 (nit)
Features
Pressure-sensitive, Ambient light sensor Pressure-sensitive, Scratch-resistant glass (Sapphire), Ambient light sensor

Hardware

System chip
Apple S2 (16 nm) Apple S4 (7 nm)
Processor
Dual-core
780 MHz
Cortex-A7
Dual-core
GPU
PowerVR G6200 Apple G11M
RAM
0.5GB 1GB
Internal storage
8GB 16GB
Storage expansion
not expandable not expandable
OS
watchOS (6.x, 5.1, 5, 4.x, 3.x) watchOS (9.x, 8.x, 7.x, 6.x, 5)

Battery

Capacity
273 mAh 225 mAh
Charging
Magnetic charging Magnetic charging

Camera

Connectivity & Features

Bluetooth
4.0 5.0
WLAN
802.11 b,g,n 802.11 b,g,n
Location
Glonass, Galileo Glonass, Galileo, QZSS
Sensors
Accelerometer, Gyroscope, Heart rate Accelerometer, Gyroscope, Heart rate, Barometer
Other
NFC NFC

Multimedia

Speakers
Loudspeaker Loudspeaker
Additional microphone(s)
Noise cancellation

Cellular

Data Speed
LTE, HSPA
SIM type
eSIM

Alternative variants

With aluminum frame
Weight 0.99 oz (28.2 g)
Materials Frame: Aluminum
With stainless steel case
Weight 1.40 oz (39.8 g)
Materials Frame: Stainless steel
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