Overview

• Apple lists up to 42 hours of typical use for Ultra 3, up to 72 hours in Low Power Mode, and up to 20 hours for GPS plus heart‑rate workouts in Low Power Mode.
• Fast charging is rated at about 45 minutes to around 80% and roughly 75 minutes to full, with 15 minutes providing about 12 hours of normal use and 5 minutes covering about 8 hours of sleep tracking.
• Compared with Ultra 2, normal-use endurance rises from 36 to 42 hours, while Low Power Mode remains unchanged at up to 72 hours.
• Recent reporting highlights that Apple’s latest battery estimates for Ultra 3 and Series 11 include six hours of sleep tracking, meaning the improvement does not equate to six extra hours of active daytime use.
• Analysts note the clearest gains appear during workouts with GPS and heart-rate monitoring, and they recommend Low Power Mode, reduced GPS/cellular use, dimmer displays, fewer background tasks, and software updates to extend runtime.