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If you are an expat, international worker, or frequent traveler like me, you will eventually bring electronic devices across borders. Many people misunderstand how this works, but it is actually simple once you understand a few basic concepts. In most cases, you can safely use your devices abroad with little or no additional cost.
One common misconception is that you need a step up or step down transformer for almost everything. Many travelers spend fifty to one hundred dollars on bulky transformers they do not need. The reality is that most modern electronics already support global voltage ranges. In many situations, all you need is a simple plug adapter.
Plug Types
A plug adapter does not convert electricity. It simply changes the physical shape of your plug to match the local outlet. Many countries also share similar plug types. For example, most two prong US devices work in Japan without any adapter. The only exception is devices with three prong US plugs, which require a small and inexpensive three to two prong adapter. Some hotels even provide universal adapters, so you often do not need to buy anything.
If you do need an adapter, it is usually a cheap and straightforward purchase. A US to Hong Kong adapter, for example, works in several countries including the United Kingdom.
Voltage, Wattage, and Frequency
Voltage differences are where most travelers get confused. A device’s power supply has two important ratings:
Input: the type of power coming from the wall
Output: the power delivered to your device
Your electronic device only cares about the output. That does not change by country. The input changes depending on where you are:
- United States: 110 V / 60 Hz
- Japan: 100 V / 50 or 60 Hz
- United Kingdom: 220 to 240 V / 50 Hz
In most cases, devices can operate safely across these ranges. For example, I lived in Japan for eight years and used my US computer and audio equipment without any transformer. They still work today. The only device that gave me trouble was a professional hair trimmer that was designed strictly for 110 V at 60 Hz. When I moved to Tokyo, where power runs at 50 Hz, the motor produced a loud hum because it was not designed for that frequency.
These cases are rare. Most manufacturers design their devices for the global market, which brings us to the key rule:
How to Check if Your Device Will Work Abroad
Look at the power information on your device’s power supply. Most chargers and power bricks list something like:
Input: 100 to 240 V, 50 to 60 Hz
If you see this, your device will work in almost any country. This is common for phones, tablets, laptops, game consoles, and many small electronics. In these situations, all you need is a plug adapter.
Take a look around your home. You will likely notice that many devices support the full 100 to 240 V range.
What if My Device Only Supports 110 V or Only 220 V?
If your device does not support the voltage of the country you are visiting, you still have a few options before buying a transformer.
1. Check if the manufacturer sells a power supply for your destination country.
For example, my Japanese Xbox 360 came with a 100 to 110 V power supply. In the UK, where outlets run at 220 V, plugging it in would have damaged the console. Instead of buying a transformer, I purchased a used UK power supply for about fifteen pounds. Everything worked perfectly.
2. Look for an aftermarket power supply.
Some devices use standard connectors, making it possible to buy a compatible third party power supply. For instance, my Cisco Linksys router used a common 2.1 mm plug. I found a UK compatible 220 V power supply with the correct output (12 V, higher amperage is fine) and used it without issue.
If neither option works, then a transformer may be your only choice.
When a Transformer Makes Sense
Transformers can be expensive and bulky, and they are not ideal for high wattage appliances. For example, my rice cooker from Japan consumed 1400 watts. A transformer capable of safely handling that load would cost over one hundred dollars and would be massive. In cases like that, it is usually better to sell the device and buy a new one locally.
However, for low wattage devices, transformers can be reasonable. We brought a Sharp Plasmacluster air purifier from Japan that consumes only 14 watts. A small twenty dollar transformer works perfectly.
A Note for Gamers
For Xbox 360 owners, remember that the console is region locked. A UK console cannot play many US or Japanese games. However, most modern televisions support both NTSC and PAL formats, so TV compatibility is not an issue.
What started as a quick write up turned into a detailed guide, but I hope it helps simplify what can be a confusing topic for many travelers. In most cases, using your devices abroad is much easier than people assume. A little knowledge and a simple plug adapter go a long way.