Apple Watch Series 5Apple Watch Series 4Apple Watch Series 3
Tech specs 
Size40 mm (band fits 130-200mm wrists)
44 mm (band fits 140-210mm wrists)
40 mm (band fits 130-200mm wrists)
44 mm (band fits 140-210mm wrists)
38.6mm x 33.3mm x 10.7mm (H x W x D)
32.0mm x 35.9mm x 10.7mm (H x W x D)
MaterialAluminium, stainless steel, titanium and ceramic case options.
Ion-X strengthened glass; Sapphire crystal and ceramic back
Sapphire crystal and ceramic back.Aluminum, Ceramic (White, Black), Sapphire Crystal, Gold Aluminium, Stainless Steel (Silver, Black)
ChargingWireless chargingWireless chargingwireless charging
BatteryLithium-ionLithium-ionLithium-ion
Battery life18+ hours18+ hours18+ hours
Water-resistance5 ATM (50 metres)5 ATM (50 metres)5 ATM (50 metres)
WeightCase weight: 30.1g (for 40mm version); 36.7g (for 44mm version)Case weight: 30.1g (for 40mm version); 36.7g (for 44mm version)53 grams
SensorAmbient light, optical heart rate sensor, Electrical heart sensor, improved accelerometer up to 32 g‑forces, improved gyroscope, GPS (GLONASS, Galileo, and QZSS), barometric altimeter, ambient light sensor, compassAmbient light, optical heart rate sensor, Electrical heart sensor, improved accelerometer up to 32 g‑forces, improved gyroscope, GPS (GLONASS, Galileo, and QZSS), barometric altimeter, ambient light sensorAmbient light, heart rate sensor, accelerometer, gyroscope, GPS, barometric altimeter
DisplayAlways-On Retina display with Force Touch, LTPO OLED display (1000 nits)LTPO OLED Retina display with Force Touch (1000 nits), Ion-X strengthened glassOLED Retina display with Force Touch
Ion-X glass (strengthened glass)
Screen size44mm: 977 sq mm display area
40mm: 759 sq mm display area
44mm: 977 sq mm display area (368 x 448 pixel resolution)
40mm: 759 sq mm display area (324 x 394 pixel resolution)
38mm: 340x272 pixels
42mm: 390x312 pixels
ColorsA number of aluminum finishes anodized in silver, gold and space gray. You can also pick up the device in gold stainless steel with a matching Milanese band, joining the silver and space black stainless steel models.A number of aluminum finishes anodized in silver, gold and space gray. You can also pick up the device in gold stainless steel with a matching Milanese band, joining the silver and space black stainless steel models.Gold, Rose Gold, Space Gray, Silver, Black. Straps vary by editions.
OtherPLATFORM: watchOS
PROCESSOR: S5 with 64-bit dual-core processor, W3 Apple wireless chip
MEMORY: 512 RAM, 32GB storage
CONNECTIVITY: Bluetooth 4.0, NFC, WiFi, LTE and UMTS cellular radio
PLATFORM: watchOS
PROCESSOR: S4 with 64-bit dual-core processor, W3 Apple wireless chip
MEMORY: 512 RAM, 16GB storage
CONNECTIVITY: Bluetooth 4.0, NFC, WiFi, LTE and UMTS cellular radio
PLATFORM: watchOS
PROCESSOR: S3 dual-core processor
MEMORY: 512 RAM, 16GB storage
CONNECTIVITY: Bluetooth 4.0, NFC, WiFi, LTE and UMTS cellular radio
Activity tracking 
StepsYesYesYes
DistanceYesYesYes
Calories burnedYesYesYes
ActivityYesYesYes
FloorsYesYesYes
SleepYesYes
Heart rateYesYesYes
Stress & recovery
Pulse Ox
Respiration rate
UV exposure
Skin temperature
Galvanic skin response
Hydration level
Calorie intake
GPSYes (GPS,GLONASS, Galileo, and QZSS)Yes (GPS,GLONASS, Galileo, and QZSS)Yes
Running featuresWatch displays up to 5 metrics during your run (time, distance, current pace and average pace, heart rate, active calories or total calories).Watch displays up to 5 metrics during your run (time, distance, current pace and average pace, heart rate, active calories or total calories).Watch displays up to 5 metrics during your run (time, distance, current pace and average pace, heart rate, active calories or total calories).
Swimming featuresPool swim and open water swim. At the end of a swim, the watch displays the time of day the activity took place, dominant stroke used (auto-detection is used), distance, workout time, pool length, laps completed, average pace, average heart rate, and both active and total calories burned, as well as the weather at your location. Pool swim and open water swim. At the end of a swim, the watch displays the time of day the activity took place, dominant stroke used (auto-detection is used), distance, workout time, pool length, laps completed, average pace, average heart rate, and both active and total calories burned, as well as the weather at your location. Pool swim and open water swim. At the end of a swim, the watch displays the time of day the activity took place, dominant stroke used (auto-detection is used), distance, workout time, pool length, laps completed, average pace, average heart rate, and both active and total calories burned, as well as the weather at your location.
Other - ECG monitor
- irregular heart rate detection
- low or high heart rate alerts
- fall detection
- ECG monitor
- irregular heart rate detection
- low or high heart rate alerts
- fall detection
Non-fitness functions 
Smartphone notificationsYesYesYes
On-board music storageYes (Stream Apple Music direct to watch)Yes (Stream Apple Music direct to watch)Yes ( Stream Apple Music direct to watch)
Connected payYesYesYes
LTEYesYesYes
Links 
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