The Apple Watch Series 12 reaches 80 percent in about 30 minutes and the Apple Watch Ultra 4 in about 45 minutes, according to Apple’s tech specs. That looks like a win for the smaller watch, but the Ultra has a battery rated at more than twice the hours, and its 15-minute top-up buys 18 hours of normal use against 12 hours on Series 12. Here are all the charging figures Apple has published for both watches, plus last year’s models for context.
Charging is the spec Apple leaned on hardest this year. The Series 12 press release calls its 15-minute charge 50 percent faster than before, and the Ultra 4 press release lists a 15-minute charge as good for 18 hours where the Ultra 3 managed 12. The 80 percent times did not change on either watch. Read our Series 12 launch story and Ultra 4 launch story for the full announcements.
Series 12 vs Ultra 4 charging table
| Charging figure | Series 12 | Ultra 4 | Series 11 | Ultra 3 |
|---|---|---|---|---|
| Fast charge to 80 percent | About 30 min | About 45 min | About 30 min | About 45 min |
| 15-minute charge | Up to 12 h normal use | Up to 18 h normal use | Apple has not published | Up to 12 h |
| 5-minute charge | Up to 10 h sleep tracking | Up to 10 h sleep tracking | Apple has not published | Apple has not published |
| Battery, normal use | Up to 24 h | Up to 50 h | Up to 24 h | Up to 42 h |
| Low Power Mode | Up to 38 h | Up to 84 h | Up to 38 h | Up to 72 h |
| Charger in the box | Magnetic Fast Charger to USB-C (1 m) | Magnetic Fast Charger to USB-C (1 m) | Apple has not published | Magnetic Fast Charger to USB-C (1 m) |
80 percent in 30 minutes vs 45 minutes
The Series 12 charges to 80 percent in about 30 minutes, the same as the Series 11 on Apple’s compare page. The Ultra 4 takes about 45 minutes, again matching its predecessor. Apple’s SE 3 tech specs also list about 45 minutes.
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The reason the smaller watch wins on this metric is simply capacity. Series 12 is rated for 24 hours of normal use, the Ultra 4 for 50 hours. Apple has not published battery capacity in milliampere hours or watt hours for either watch, so the hours ratings are the only way to size them.
The 15-minute top-up: 12 hours vs 18 hours
Measured by what you get for a quarter of an hour on the puck, the Ultra 4 comes out ahead. Apple’s tech specs say 15 minutes gives up to 18 hours of normal use on Ultra 4 and up to 12 hours on Series 12.
That 18-hour figure is the Ultra 4’s biggest charging improvement. The Ultra 3 tech specs list 12 hours from the same 15 minutes, so the new watch delivers 50 percent more use from an identical stop. Series 12’s 12-hour figure is also described by Apple as 50 percent faster than before, but Apple has not published the Series 11’s 15-minute figure on the pages we checked, so we cannot show the earlier number.
Five minutes for a night of sleep tracking
Both new watches share one rating: a five-minute charge is good for up to 10 hours of sleep tracking. Apple published this for Series 12 and Ultra 4 but not for the Ultra 3 or SE 3, so it appears to be a new line on the spec sheet rather than a changed figure.
In practice, this is the number that matters if you wear the watch overnight. Five minutes on the charger while you brush your teeth covers a full night of sleep score and sleep apnea data on either watch, and the Ultra 4 will still have more left over in the morning because it started from a larger battery.
What is in the box, and what Apple has not said
Both watches ship with the Apple Watch Magnetic Fast Charger to USB-C Cable (1 m). Neither includes a power adapter, and Apple has not published which adapter wattage its charging times assume, so the 30 and 45-minute figures should be read as Apple’s best case.
Apple’s charging ratings are all listed as up to figures and depend on settings and use. If you are choosing between the two watches on charging alone, the Series 12 is the one that leaves the puck sooner, while the Ultra 4 is the one that goes longer between visits. Both are available September 18, with pre-orders open now.
