So Apple is hyping the Watch Series 11 as having 24 hours of battery life compared to 18 hours on the Series 10. That looks like a huge 33% improvement, moving away from their 18h goalpost for the first time ever since the very first Watch. But if you read their testing methodology in the footnotes it’s not really what it seems.

Here’s what Apple says:

• Series 11 (24h test): 300 time checks, 90 notifications, 15 min of app use, a 60-min workout with music playback, plus 6 hours of sleep tracking.

• Series 10 (18h test): 300 time checks, 90 notifications, 15 min of app use, a 60-min workout with music playback. No sleep tracking included.

That’s the whole difference. The “extra 6 hours” is just Apple finally including sleep tracking in the test. But sleep tracking barely sips power, and previous Apple Watches have already been able to easily surpass their 18 hour claims and go through a night of sleep tracking on top.

But fine, we can't be sure without actually having the Watch and testing it out. Thankfully, Apple provides us with another claim, Low Power Mode:

• Series 11 (38h test): 530 time checks, 160 notifications, 26 min of app use, 60-min workout, and 6 hours of sleep tracking.

• Series 10 (36h test): 600 time checks, 180 notifications, 30 min of app use, 60-min workout.

So here, not only is the difference just 2 hours (38 vs 36), a measly 5% increase, but even then Apple also quietly lowered the “active usage” assumptions for the new model. Fewer checks, fewer notifications, less app time. Again, not really an upgrade, just a shift in methodology.

So the headline "24h battery" isn’t an actual hardware improvement. It’s just marketing.

Given that hypertension monitoring and sleep score is coming to older Watches via an update anyways, the only things new with the Series 11 are the ceramic coating on the display and 5G (lol). Oh right, and a slightly lighter Space Gray, tweaked for the millionth time. Not even the chip got a number upgrade, they usually do that even though the chip itself stays the same. Should Apple switch to a bi-yearly upgrade cycle like they did with the Ultra?

Sources:
Series 11 Series 10 (via Wayback Machine)

Edit: I admit scam is a bit harsh, I would change the title if I could. But still, Apple marketing 33% improvement (even if technically correct in this very specific circumstance) while their other, more comparable, test only claims 5% is kind of scummy in and of itself.

nearly a full 48 hours on a single charge. Mind you my use is not super heavy, I didn’t do any workouts but for general notifications, two nights of sleep tracking and all sensors turned on, and probably 2 hours of music playing off the watch I’m very happy with the battery life so far.

Had my first full battery cycle and did some charge testing with my new Series 11 (GPS + Cellular) 42mm.

TL;DR: battery lasted 33h 45min, charging 0-100% takes 1h 12min, didn’t meet Apple’s claims of 0-80% in around 30min.

Managed to get 33h 45min of battery life (12 a.m. on Friday to 9:45 a.m. on Saturday), of which 14h 25min were sleep tracking and 50min were an Outdoor Walk workout. I don’t use the AOD or noise monitoring and haven’t set up cellular yet. Pretty decent, but I was hoping for a bigger difference considering the improvement in battery life is the Series 11’s only major feature; my 41mm GPS Series 7 got around the same battery life as this when it was new. Maybe it’ll improve after a few days or over the next few watchOS versions; this is its first charge cycle after all.

I’ve charged the watch twice so far, one time with the included A2515 braided charging cable (first chart) and one time with the A2515 charging cable that came with my Series 7 (second chart), both using an A2676 35W Dual USB-C Port Power Adapter, and got pretty much the same time between putting the watch on the charger and reaching 100% on both tests, around 1h 12min. Apple claims that the Series 11 can go from boot to 80% in around 30min, but in my testing, it took 42-44 minutes to reach 80%, not sure what’s up with that.

Overall, I’m really happy with my new watch, but at least based on these first few tests it seems like some of the improvements they claim to have made aren’t actually that significant.

Doctor here, doing on-call shifts where I absolutely need to be reachable by nurses or other colleagues. I can't miss a single call.

I'm considering an Apple Watch Series 11 Cellular as a reliable backup if my phone dies or restarts unexpectedly (especially overnight).

What's the battery life like with constant cellular use (frequent notifications, occasional calls, overnight standby)? Any healthcare or on-call workers using it this way?

Thanks for sharing your experiences!