Apple Watch Battery to Last 18 Hours, 72 Hours in Power Reserve

Just as Apple has posted a detailed Apple Watch ‘Sizing Guide’ for various watch bands to help you better decide which one to pre-order on April 10, it has also published a comprehensive Apple Watch battery information page on its website, highlighting its ‘all-day battery life’ of up to 18 hours, which can be extended to almost 72 hours if the watch is used in Power Reserve mode.


Apple notes that its battery tests were performed using preproduction Apple Watch and software paired with an iPhone using preproduction software, which means actual results may vary. Regarding the ‘all-day battery life’ claim, Apple says it is based on 90 time checks, 90 notifications, 45 minutes of app use, and a 30-minute workout with music playback from Apple Watch via Bluetooth, over the course of 18 hours.

The most interesting battery feature of the Apple Watch is perhaps is the ‘Power Reserve’ mode, which kicks in automatically if the battery gets too low. “Apple Watch automatically switches into Power Reserve mode so you can continue to see the time for up to 72 hours”.

Below is a list of results extracted from Apple’s extensive battery testing of the Apple Watch:

  • All-Day Battery Life : Up to 18 hours
  • Audio Playback Test : Up to 6.5 hours
  • Workout Test : Up to 7 hours
  • Watch Test : Up to 48 hours
  • Power Reserve : Up to 72 hours





Apple also highlights that it takes 1.5 hours for the Apple Watch to reach 80% charge and 2.5 hours to reach 100%. Also, the above mentioned performance claims are based on test results from the 38mm Apple Watch, while the 42mm Apple Watch will have longer battery life.