Apple Watch SE 3 vs Apple Watch Series 6

Every spec side by side, from each maker's published figures.

Better figure, where one is clearly better

Watch SE 3 compared with Watch Series 6
AppleWatch SE 3AppleWatch Series 6
Overview
ReleasedSeptember 2025September 2020
Display
Case sizes40 mm or 44 mm40 mm or 44 mm
PanelLTPO OLEDLTPO OLED
Peak brightness1,000 nits1,000 nits
Always-on displayYesYes
Display detailAlways-On Retina display with OLED and LTPO; 324 x 394 pixels (40mm) or 368 x 448 pixels (44mm) at 326 ppi; 759 or 977 sq mm display area; 2 nits minimum brightnessAlways-On Retina LTPO OLED; 40mm 324 x 394 pixels and 759 sq mm; 44mm 368 x 448 pixels and 977 sq mm; wrist-down outdoor brightness up to 2.5 times Series 5
Screen protectionIon-X front glass, 4x more crack resistant than SE 2–
Health and fitness
ECGNoYes
Blood oxygenNoYes
Skin temperatureYesNo
Sleep apnoea alertsYesNo
High blood pressure alertsNoNo
Body compositionNoNo
Fall detectionYesYes
Crash detectionYesNo
GPSSingle-bandSingle-band
Water resistance50 m50 m
SensorsSecond-generation optical heart sensor; temperature sensor; compass; always-on altimeter; high-g accelerometer; high dynamic range gyroscope; ambient light sensorBlood oxygen sensor; electrical and third-generation optical heart sensors; compass, always-on altimeter, accelerometer up to 32 g-forces, gyroscope and ambient light sensor
Health featuresHeart Rate app; high and low heart rate notifications; irregular rhythm notifications; sleep apnoea notifications; sleep stages and sleep score; Vitals app (heart rate, respiratory rate, wrist temperature and sleep duration); Cycle Tracking with fertile window and retrospective ovulation estimates, perimenopause and menopause support; Medications; Mindfulness; NoiseECG and Blood Oxygen apps, irregular-rhythm notifications; sleep tracking and automatic handwashing detection in watchOS 7; oxygen readings are for general wellness rather than medical use
Fitness featuresCustom workouts; Training Load; customisable heart rate zones; VO2 max; Race Route; Pacer; cadence, stride length, ground contact time, vertical oscillation and running power; automatic track detection; multisport workouts; offline maps with custom route creation; Backtrack; pool and open-water swimming with SWOLF; cycling power zones with Bluetooth accessories; GymKitGPS/GNSS and GymKit; always-on elevation tracking; dance, core training, functional strength training and cooldown workouts in watchOS 7
Safety featuresEmergency SOS; international emergency calling; Fall Detection; Crash Detection; Check In; Backtrack; noise monitoringFall detection and Emergency SOS; international emergency calling on cellular versions in supported regions
Battery and connections
Battery life (maker's claim)Up to 18 hoursUp to 18 hours
In low-power modeUp to 32 hours–
Mobile data optionYesYes
Works withiPhoneiPhone
ChipS10S6
Storage64 GB (better)32 GB
Battery life detailUp to 18 hours of normal use; up to 32 hours in Low Power Mode; up to 7 hours of outdoor workoutBuilt-in rechargeable lithium-ion battery
ChargingFast charging to 80% in about 45 minutes; 15 minutes for up to 8 hours of normal use; 8 minutes for up to 8 hours of sleep tracking1 m magnetic charging cable; full charge in under 1.5 hours, according to Apple's launch announcement
ConnectivityWi-Fi 4 (802.11n) at 2.4GHz; Bluetooth 5.3; NFC for Apple Pay; L1 GPS (GLONASS, Galileo, QZSS and BeiDou); GPS + Cellular models (A3326, A3328) with 5G RedCap and LTEW3 wireless chip and U1 Ultra Wideband chip; Wi-Fi 802.11b/g/n at 2.4GHz and 5GHz; Bluetooth 5.0; cellular versions add LTE and UMTS; requires iPhone 6s or later with iOS 14 at launch
Design
Weight (lightest version)26.3 g (better)30.5 g
SoftwarewatchOSwatchOS
Case materials100% recycled aluminium case with nylon composite and sapphire crystal back; water resistant to 50 m (ISO 22810:2010)Aluminium, stainless steel or titanium; ceramic and sapphire crystal back; 50 m rating under ISO 22810:2010 for shallow-water swimming
Size40mm is 40 x 34 x 10.7 mm, 26.3 g (GPS) or 26.4 g (GPS + Cellular); 44mm is 44 x 38 x 10.7 mm, 32.9 g (GPS) or 33.0 g (GPS + Cellular)40mm 40 x 34 x 10.7 mm, aluminium 30.5 g, steel 39.7 g or titanium 34.6 g; 44mm 44 x 38 x 10.7 mm, aluminium 36.5 g, steel 47.1 g or titanium 41.3 g; case weights exclude bands
BandsFits 130–200 mm wrists (40mm) or 140–245 mm wrists (44mm)Apple Watch Studio offers case and band choices; Solo Loop and Braided Solo Loop introduced with Series 6; Nike and Hermès bands and faces also offered
ColoursMidnight or Starlight aluminiumSilver, Space Grey, Gold, Blue or (PRODUCT)RED aluminium; Silver, Graphite or Gold stainless steel; natural or Space Black (DLC) titanium; Nike Silver or Space Grey; Hermès steel or Space Black steel
In the boxApple Watch SE 3, strap, Apple Watch Magnetic Fast Charger to USB-C Cable (1 m)Watch, band or loop and 1 m magnetic charging cable; no USB power adapter

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