Apple Watch Series 4 and 5 Will Recalibrate Maximum Battery Capacity With watchOS 9

With watchOS 9, Apple is adding a new recalibration feature for the Apple Watch Series 4 and Apple Watch Series 5, according to the watchOS 9 release notes. The recalibration will result in a more accurate estimate for maximum battery capacity.

apple watch series 5

After updating to watchOS 9, your Apple Watch Series 4 or Series 5 will recalibrate and then estimate its maximum battery capacity more accurately.

Following the watchOS 9 update, Apple Watch Series 4 and Series 5 owners who have noticed battery life being misrepresented should be able to get a better read on how long their device will last.

Apple has previously introduced recalibration functionality for the iPhone 11 to make ‌iPhone‌ battery life estimates more accurate, but there has been no similar feature made available for the Apple Watch until now.

The recalibration process will happen during the update and will be complete once it's installed.

Related Roundup: watchOS 26
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Top Rated Comments

applefanboysince93 Avatar
43 months ago
instead of a %batteryLife estimate there’ll be a $BuyANewWatch message ;)
Score: 16 Votes (Like | Disagree)
Blackstick Avatar
43 months ago
End of the day... the issue is those cells are pushing 4 years old in the case of a well used/loved Series 4. Software optimization can only go so far when you're talking about a 4 year old battery with 1400 cycles on it.
Score: 9 Votes (Like | Disagree)
wwooden Avatar
43 months ago
My Series 4 is at 80% battery health. Doesn't affect any of my day-to-day: I still can workout in the morning, wear it all day at work, and still do more activities in the evening before it starts to get close to 15-20%. When it starts affecting my daily activities, I'll just pay to get the battery replaced. The feature set of the Series 4 meets all my needs.
Score: 3 Votes (Like | Disagree)
SantaFeNM Avatar
43 months ago

For a $79 battery replacement fee does the Apple Store change the battery or just give you a new AWS4?
I had the battery replaced in my AW S4 in March of 2021. I had a significant scratch on the screen when I sent it off. Apple sent back to me a new AW S4, of course with a new battery and pristine screen. A big win-win in my case and opinion.
Score: 3 Votes (Like | Disagree)
Shirasaki Avatar
43 months ago
My series 4 still hold strong after all these years (4 years). 88% battery health. Good enough feature set to last incredibly long. Wonder how this “calibration” would work.
Score: 3 Votes (Like | Disagree)
HappyDude20 Avatar
43 months ago
For a $79 battery replacement fee does the Apple Store change the battery or just give you a new AWS4?


Not applicable to my S5 since I will not be downloading iOS 16 until next Summer, at the earliest.
Why holding out?
Score: 2 Votes (Like | Disagree)