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.