The electric supply in Japan is 100V (compare to 110-120V in the US, 220V elsewhere). Most devices these days can handle that just fine so you won’t need a transformer. Japan’s wall outlets are generally compatible with US plugs. The most common kind is a two-prong outlet, but in some (rare) cases a three-prong may be available (we found them on some hotel desks, ostensibly for computers, and for hair dryers in bathrooms).

Because of plug compatibility the only problems you may run into are:

• Your device has a three-prong plug, but the outlet is two-prong
• You cannot find enough wall outlets
• Wall outlets are too far away from where you want something plugged in (not atypical in hotels)

The first problem can be addressed with an adapter, such as this one. Many other brands are available and you can get them online or at your local hardware store.

The second problem can be addressed with a small power strip. I actually use this one, which combines only needing a two-prong wall outlet with providing multiple outlets in both two- and three-prong formats. These kind of power strips can come with long or short cords. I liked this one because it had a long cord. It proved useful during the trip.

Another, or additional, option is to use a multi-port charger like this one. These require only one outlet, but provide multiple USB-C and USB-A ports. There are different models, of different total capacities, with different amounts and mixes of ports. Bringing even one of these often allows two person’s (multiple) devices to all charge from it. The cords on these are somewhat long, so may also address the third problem.

I brought the second and third option, removing the need for the adapter.

An optional, but handy gadget

A while ago I realized that when travelling I often don’t like the alarm clocks provided, if at all. They are all different, and outdated. You have to figure each one out, and hope they are not broken etc. At home, I always use my iPhone or watch to set and handle alarms, so why not when travelling?

There are devices that provide a stand for your iPhone using a MagSafe adapter. It securely holds the phone while simultaneously wirelessly charging the phone. Combine this with the iPhone’s standby mode: iPhone’s StandBy mode, introduced with iOS 17, transforms the locked iPhone into a smart display when charging and placed horizontally. It shows customizable widgets, photos, or a large clock. To activate it, the iPhone must be locked, placed horizontally on a charger, and charging. StandBy mode is designed to be used while charging, typically on a nightstand or desk.

The simplest of these devices (example) offer just a stand and charging for the phone, but more sophisticated ones also include a pad for wirelessly charging an AirPods case and possibly a third option for an Apple Watch. I am using this at home, but found a nice compact one that I got for travel purposes. These are not necessarily cheap, but awfully handy. Using it also reduces the need for charging ports and cables from three to one, leaving more ports for other devices or travel companions.