Apple’s claim that the Apple Watch Series 11 offers 24 hours of battery life has come under scrutiny, as a closer examination of Apple’s testing data reveals that the increase from the Series 10’s 18-hour rating is largely attributable to changes in testing methodology rather than significant hardware changes.
Apple lists the Apple Watch Series 11 as capable of lasting up to 24 hours on a single charge, a significant increase over the Series 10 claim, which has been the company’s published standard since the launch of the original Apple Watch in 2015.
As spotted by a user on the MacRumors forums, the main difference between the two test scenarios in Apple’s official documentation is the inclusion of sleep tracking in the Series 11’s rating. Apple says the 24-hour figure is based on 300 time checks, 90 notifications, 15 minutes of app use, 60 minutes of exercise with music playback, and six hours of sleep tracking. The comparable Series 10 test lists the same parameters but does not include sleep tracking.
While Apple doesn’t break down the exact battery drain of each activity, sleep tracking is typically a low-power feature, allowing older Apple Watch models to be worn overnight without completely draining their battery. Many users have noted that Apple Watches have long exceeded the company’s stated 18-hour battery life in real-world use, with most users comfortably reaching the tracking mark overnight. This suggests that the six-hour increase is largely due to Apple adding sleep tracking to its official story, rather than a significant increase in real-world battery life.
Apple also publishes estimates for low-power mode battery life, which further show only modest changes. The Series 11 is rated for 38 hours of battery life in low-power mode, compared to the Series 10’s 36-hour rating. Here, Apple’s footnotes point out that the Series 11’s test used a lower level of activity: 530 time checks, 160 notifications, and 26 minutes of app use, compared to 600 time checks, 180 notifications, and 30 minutes of app use for the Series 10. Both tests included a 60-minute workout and six hours of sleep tracking. The reduced activity assumptions make it difficult to compare them directly, but even Apple’s own hourly estimate only amounts to about an 8% improvement.
The Apple Watch Series 11 has slightly larger batteries across its range of case sizes. According to the official safety documentation, the battery capacity of the Series 11 models ranges from 1,245 to 1,403 watt-hours, depending on the case size, compared to 1,118 to 1,266 watt-hours for the Series 10 models. That’s a roughly 7% to 10% increase, which is much smaller than the 33% jump that Apple’s move from 18 hours to 24 hours claim implies.
