1. Plug type and voltage are different things
The plug type decides whether you can physically connect; the voltage decides whether the device works safely.
Common plug types include A, B, C, E, F, G and I. Mains voltage mostly comes in two ranges: 110–120V (North America, Japan and others) and 220–240V (Europe, most of Asia and others).
2. Read the power label first
Phone, laptop and camera chargers usually say 100–240V ~ 50/60Hz, meaning they are dual-voltage and only need a plug adapter.
If a device says only 110V or 220V, it needs a converter, or it can be damaged.
3. Plugs and voltage in common destinations
Mainland China is mostly A/C/I at 220V; Hong Kong is G at 220V; Taiwan is A/B at 110V; Japan is A/B at 100V; the United States and Canada are A/B at 120V; the UK and Singapore are G at 230V; most of the EU is C/E/F at 230V; Australia is I at 230V.
Several standards can coexist in one country, so verify the sockets and the latest standards at your destination.
4. Adapter versus converter
A plug adapter only changes the shape; a converter steps the voltage down and must match the device's wattage.
Most USB chargers are dual-voltage and only need an adapter. High-wattage devices such as hair dryers and curling irons need a voltage and wattage check.
5. Common mistakes
Common mistakes include plugging a 110V device into a 220V socket, using an underpowered converter for a high-wattage device, treating a travel adapter as a voltage converter, and ignoring frequency differences for motor-driven devices.
Electronics rated 50/60Hz are not affected by frequency; motor-driven devices such as electric shavers need extra care.
6. Checklist before departure
Before departure: read the power label on each device; count how many devices will charge at once; carry a dual-voltage adapter with USB/USB-C output; and confirm voltage and wattage separately for high-wattage devices.