iPhone Duo Charging Test: 1h40m Open, 12 Minutes Slower Closed
The iPhone Duo peaks at 42W — even on Apple's 60W charger, so your existing 30W brick is only 3 minutes slower. Full charge takes 1h40m unfolded but 1h52m folded, because trapped heat throttles charging when shut.
Wireless is 15W official, up to 33W on select third-party MagSafe chargers — but check case compatibility first, since some cases interfere with the hinge magnets. Battery life tracks screen utilization more than clock time: dark and folded sips, bright full-screen drinks.
The charging numbers, all in one table
| Scenario | Result |
|---|---|
| 0–100% unfolded | 1h 40m |
| 0–100% folded | 1h 52m — 12 min slower |
| Peak wired power | 42W (even on Apple's 60W charger) |
| 30W PD charger | 1h 43m — just 3 min slower than 65W |
| 20-min top-up | 42% — bottom of the pack vs Samsung and other iPhones |
| Wireless (official MagSafe) | 15W max |
| Wireless (select third-party) | up to 33W |
Why is folded charging slower?
The 12-minute gap is thermal. Folded shut, the Duo becomes a 'display sandwich' — heat generated inside struggles to escape, so the phone reduces charging power to protect itself. The gap should widen in summer. Ironic consequence: the natural way to charge a foldable (closed, out of the way) is the slower way.
The 42W cap: don't overspend on the charger
Apple's spec sheet suggests a 60W charger for fast charging. The phone never draws more than 42W. A standard 30W PD charger — the one you probably already own — fills the unfolded Duo in 1h43m, just 3 minutes behind a 65W brick. Don't buy the expensive charger for this phone.
Wireless: 15W official, 33W third-party — with a catch
Official MagSafe tops out at 15W, but reviewers measured up to 33W on select third-party MagSafe chargers — unusually fast for wireless. One warning from testing: the Duo's hinge area has unusual magnets, and some third-party cases interfere with them, making wireless charging unstable. If you buy a case, confirm wireless charging still works — or stick to Apple's official case, which tested fine.
How long does the battery actually last?
Heavy-use test: 5h 29m — beating the iPhone Air and 18 Pro, trailing the Pro Max. But 影视飓风 found the interesting pattern: battery drain tracks screen utilization, not time. Recording video for 2 hours (lots of black pixels): Duo kept 61%, the best of the three. Watching 16:9 video for 3 hours (full screen lit): Duo kept only 84%, the worst. Translation: light, dark, and folded use sips power; bright full-screen use drinks it. Everyday mixed use should still last a full day.
Known pain points
- Apple lists a 60W charger for 'fast charging' but the phone caps at 42W — the expensive first-party brick buys you almost nothing.
- Folded charging is slower because of heat — the phone punishes you for the natural way to charge it.
- Some third-party cases interfere with the hinge magnets and make wireless charging unstable; case shopping needs research.
Quick answers
What is the iPhone Duo's max charging speed?
Does the iPhone Duo charge slower when folded?
How fast is iPhone Duo wireless charging?
📺 Review sources (3) — every number above comes from these hands-on tests
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