watchOS 9.4 to Recalibrate Battery Capacity on 44mm Apple Watch Series 6

The watchOS 9.4 update that Apple is beta testing right now will include a battery recalibration process for the 44mm Apple Watch Series 6, Apple said today in an updated Apple Watch support document.

apple watch series 6 unboxing image
After updating to watchOS 9.4, the 44mm Apple Watch Series 6 will be able to estimate maximum battery capacity more accurately following the recalibration process.

Apple recalibrated the batteries of the Apple Watch Series 4 and Apple Watch Series 5 models with the watchOS 9 update, and now the process is being extended to the 44mm Apple Watch Series 6.

Battery recalibration has also been done for some iPhone models in the past, including the iPhone 11. Recalibration is able to improve inaccurate estimates of battery health that some users may be seeing.

Related Roundup: watchOS 26
Related Forum: Apple Watch

Popular Stories

iOS 26

iOS 26.4 and iOS 27 Features Revealed in New Leak

Friday December 12, 2025 10:56 am PST by
Macworld's Filipe Espósito today revealed a handful of features that Apple is allegedly planning for iOS 26.4, iOS 27, and even iOS 28. The report said the features are referenced within the code for a leaked internal build of iOS 26 that is not meant to be seen by the public. However, it appears that Espósito and/or his sources managed to gain access to it, providing us with a sneak peek...
Apple Logo Top Half

Early iOS 26 Software Leak Uncovers Dozens of Upcoming Apple Features

Monday December 15, 2025 3:05 pm PST by
Software from an iPhone prototype running an early build of iOS 26 leaked last week, giving us a glimpse at future Apple devices and iOS features. We recapped device codenames in our prior article, and now we have a list of some of the most notable feature flags that were found in the software code. In some cases, it's obvious what the feature flags are referring to, while some are more...
apple beta 26 lineup

Apple Leak Confirms Work on Foldable iPhone, AirTag 2, and Dozens More Devices

Monday December 15, 2025 2:05 pm PST by
Last week, details about unreleased Apple devices and future iOS features were shared by Macworld. This week, we learned where the information came from, plus we have more findings from the leak. As it turns out, an Apple prototype device running an early build of iOS 26 was sold, and the person who bought it shared the software. The OS has a version number of 23A5234w, and the first...
Apple Foldable Thumb

Leak Reveals Foldable iPhone Details

Monday December 15, 2025 9:09 am PST by
The first foldable iPhone will feature a series of design and hardware firsts for Apple, according to details shared by the Weibo leaker known as Digital Chat Station. According to a new post, via machine translation, Apple is developing what the leaker describes as a "wide foldable" device, a term used to refer to a horizontally oriented, book-style foldable with a large internal display....
iOS 26

iOS 26.3 Beta 1 Features: What's New So Far

Monday December 15, 2025 4:23 pm PST by
Apple is testing iOS 26.3, the next version of iOS 26 that will launch around January. Since iOS 26.3's testing is happening over the holidays, it is a smaller update with fewer features than we've seen in prior betas. We've rounded up what's new so far, and we'll add to our list with subsequent betas if we come across any other features. Transfer to Android Apple is making it simpler...
iOS 26

Apple Releases iOS 26.2 With Alarms for Reminders, Lock Screen Changes, Enhanced Safety Alerts and More

Friday December 12, 2025 10:10 am PST by
Apple today released iOS 26.2, the second major update to the iOS 26 operating system that came out in September, iOS 26.2 comes a little over a month after iOS 26.1 launched. ‌iOS 26‌.2 is compatible with the ‌iPhone‌ 11 series and later, as well as the second-generation ‌iPhone‌ SE. The new software can be downloaded on eligible iPhones over-the-air by going to Settings >...
iOS 26

iOS 26.2 Coming Soon With These 8 New Features on Your iPhone

Thursday December 11, 2025 8:49 am PST by
Apple seeded the second iOS 26.2 Release Candidate to developers earlier this week, meaning the update will be released to the general public very soon. Apple confirmed iOS 26.2 would be released in December, but it did not provide a specific date. We expect the update to be released by early next week. iOS 26.2 includes a handful of new features and changes on the iPhone, such as a new...
airpods max 2024 colors

AirPods Max 2 Likely to Offer These 10 New Features

Monday December 15, 2025 7:41 am PST by
Apple released the AirPods Max on December 15, 2020, meaning the over-ear headphones launched five years ago today. While the AirPods Max were updated with a USB-C port and new color options last year, followed by support for lossless audio and ultra-low latency audio this year, the headphones lack some of the features that have been introduced for newer generations of the regular AirPods and the ...

Top Rated Comments

surfzen21 Avatar
37 months ago
Good to still see a focus on the older models.
Score: 12 Votes (Like | Disagree)
Robert.Walter Avatar
37 months ago
My launch day 44mm 6’s battery health hung at 81-82% for months before my 2 year warranty ran out (even though it was needing to be recharged more and more frequently) and about a month after warranty ran out, it was around 77% (the batteries in my series 0 and 3 degraded much more slowly.)

Two other family members and a colleague with the same watch had better battery health, low 80’s, at the same time mine was in the mid 70’s.)

So I complained to Apple and they sent me a replacement.
Score: 12 Votes (Like | Disagree)
pcmike Avatar
37 months ago

My launch day S6 is at 80% battery health… waiting for it to hit 79% so I can get a replacement under AppleCare+.
I wonder which direction the recalibration will change battery health %
Enough to where you won’t be getting a replacement I bet ?
Score: 7 Votes (Like | Disagree)
macfacts Avatar
37 months ago

Sounds great. I love seeing support for older devices.

Randumb: seeing the red Watch featured in the OP, it seems offering Watch in multiple colors (think iMac), with matching bands, would be a big hit with the masses. People like colors.
Support is good but this could be to prevent warranty coverage by changing the battery status.
Score: 6 Votes (Like | Disagree)
Jdhommert Avatar
37 months ago
Interesting to see how this works out. I feel like my S6 Watch has maybe been the only Apple product I've owned where the battery went to crap so fast (ok ok iPhone X lol) I had assumed it was because I had always on display turned on for the first couple-few months and it ravaged the battery. My battery was draining so fast, and I turned it off and checked my battery health and it was already in the 80s. I gave my old launch day S4 to my dad, and last I looked it has better battery health than my launch day S6.

I probably have my eye on a 2024 watch as thats the rumored big updates. So if this update doesn't make me feel better about my battery lasting long enough to make it until then...and it probably won't...I'll get a used S7/8 to hold me over. Probably at S9 launch as they'll be much cheaper. Probably an 8 if I wait until then.
Score: 5 Votes (Like | Disagree)
geartau Avatar
37 months ago

My launch day 44mm 6’s battery health hung at 81-82% for month before my 2 year warranty ran out (even though it was needing to be recharged more and more frequently) and about a month after warranty ran out, it was around 77% (the batteries in my series 0 and 3 degraded much more slowly.)

Two other family members and a colleague with the same watch had better battery health, low 80’s, at the same time mine was in the mid 70’s.)

So I complained to Apple and they sent me a replacement.
same

my 6 series was stuck at 82% for over a year. that did not make any sense. i talked with apple and they said nothing was wrong and it was working fine. so there was no way to get it replaced under warranty.
Score: 5 Votes (Like | Disagree)