Apple Watch SE 3 40mm vs Apple Watch Ultra 3
Which one should you buy?
Who leads where?
- Health Sensors and FeaturesApple Watch Ultra 3
- DisplayApple Watch Ultra 3
- KasaApple Watch SE 3 40mm
- Positioning and GNSSApple Watch Ultra 3
- Battery and ChargingApple Watch Ultra 3
- Water and Dust ResistanceApple Watch Ultra 3
Wins are counted from the official values in the table below; the BUY / CONSIDER / WAIT call comes from each product's own decision box. We do not predict prices.
 AppleApple Watch SE 3 40mmNo reviews yet |  AppleApple Watch Ultra 3No reviews yet | |
|---|---|---|
| Key Differences | ||
| Case Size | 40 mm | 49 mm |
| Processor | Apple S10 | Apple S10 |
| Battery Life | up to 18 hours | up to 42 hours |
| ECG App | — | Yes |
| Water Resistance | 50m | 100m |
| Health Sensors and Features | ||
| Heart Rate Sensor | Yes | Yes |
| SpO2 Sensor | — | Yes |
| ECG Sensor | — | Yes |
| Skin Temperature Sensor | Yes | Yes |
| ECG App | — | Yes |
| Atrial Fibrillation Notification | Yes | Yes |
| Sleep Tracking | Yes | Yes |
| Fall Detection | Yes | Yes |
| Crash Detection | Yes | Yes |
| Display | ||
| Panel | OLED (LTPO) | OLED (LTPO3) |
| Resolution | 324x394 | 422x514 |
| Peak Brightness | 1000 nit | 3000 nit |
| Always-On Display | Yes | Yes |
| Kasa | ||
| Case Size | 40 mm | 49 mm |
| Case Thickness | 10.7 mm | 12 mm |
| Weight | 26.3 g | 61.6 g |
| Case Material | Aluminum | Titanium |
| Positioning and GNSS | ||
| GNSS Receiver | Yes | Yes |
| Dual-Band GNSS | No | Yes |
| GNSS Systems | GPS, GLONASS, Galileo, QZSS, BeiDou | GPS, GLONASS, Galileo, QZSS, BeiDou |
| Battery and Charging | ||
| The figure the maker states | up to 18 hours | up to 42 hours |
| What that figure measures | Normal use | Normal use |
| Charging Type | Fast charging | Fast charging |
| Water and Dust Resistance | ||
| Water Resistance | 50m | 100m |
| IP Rating | — | IP6X |
| Rated Depth | — | 40 m |
| MIL-STD-810 | — | MIL-STD-810H |
| Performance | ||
| Processor | Apple S10 | Apple S10 |
| Storage | 64 GB | 64 GB |
| Connectivity | ||
| Cellular | Optional | Optional |
| Wi-Fi | Wi-Fi 4 | Wi-Fi 4 |
| Bluetooth | 5.3 | 5.3 |
| Speaker | Yes | Yes |
| Microphone | Yes | Yes |
| Software | ||
| Operating System | watchOS | watchOS |
| Phone Compatibility | iPhone 11 or later (iOS 26+) | iPhone 11 or later (iOS 26+) |
Apple Watch Ultra 3 leads on 7 of 9 compared specs.
This table is based on manufacturers official specifications. Winning on paper does not always mean a difference in everyday use.