Plug types A to N
The International Electrotechnical Commission names the world's household plugs with letters from A to N. The US uses Type A, two flat parallel pins, and Type B, which adds a round grounding pin. Most of Europe uses round pins: Type C, the two-pin Europlug, fits the E, F, J, K and N sockets as well, and the IEC lists it for all of Europe except the UK, Ireland, Cyprus and Malta. The UK and Ireland use Type G with three rectangular blades. Australia, New Zealand and Argentina use Type I with two flat pins in a V. India uses Type D with three round pins, South Africa the larger Type M, Brazil Type N, Switzerland Type J and Italy Type L.
Plugs, voltage and frequency by destination
The table gives the socket types, voltage and frequency exactly as the IEC list by location states them. The last two columns are worked out from those: whether a US Type A or B plug has a matching socket type, and which voltage group the place is in.
| Destination | Plug types | Voltage | Frequency | US plug fits | Group |
|---|---|---|---|---|---|
| United States | A, B | 120 V | 60 Hz | Yes | 100 to 127 V |
| Canada | A, B | 120 V | 60 Hz | Yes | 100 to 127 V |
| Mexico | A, B | 127 V | 60 Hz | Yes | 100 to 127 V |
| Bahamas | A, B | 120 V | 60 Hz | Yes | 100 to 127 V |
| Dominican Republic | A, B | 110 V | 60 Hz | Yes | 100 to 127 V |
| Costa Rica | A, B | 120 V | 60 Hz | Yes | 100 to 127 V |
| Colombia | A, B | 110 V | 60 Hz | Yes | 100 to 127 V |
| Peru | A, B, C | 220 V | 60 Hz | Yes | 220 to 240 V |
| Brazil | C, N | 127 V, 220 V | 60 Hz | No | Both |
| Argentina | C, I | 220 V | 50 Hz | No | 220 to 240 V |
| United Kingdom | G | 230 V | 50 Hz | No | 220 to 240 V |
| Ireland | G | 230 V | 50 Hz | No | 220 to 240 V |
| France | C, E | 230 V | 50 Hz | No | 220 to 240 V |
| Germany | C, F | 230 V | 50 Hz | No | 220 to 240 V |
| Netherlands | C, F | 230 V | 50 Hz | No | 220 to 240 V |
| Spain | C, F | 230 V | 50 Hz | No | 220 to 240 V |
| Portugal | C, F | 230 V | 50 Hz | No | 220 to 240 V |
| Italy | C, F, L | 230 V | 50 Hz | No | 220 to 240 V |
| Switzerland | C, J | 230 V | 50 Hz | No | 220 to 240 V |
| Greece | C, F | 230 V | 50 Hz | No | 220 to 240 V |
| Iceland | C, F | 230 V | 50 Hz | No | 220 to 240 V |
| Turkey | C, F | 220 V | 50 Hz | No | 220 to 240 V |
| Israel | C, H, M | 230 V | 50 Hz | No | 220 to 240 V |
| United Arab Emirates | D, G | 230 V | 50 Hz | No | 220 to 240 V |
| South Africa | C, M, N | 230 V | 50 Hz | No | 220 to 240 V |
| India | C, D, M | 230 V | 50 Hz | No | 220 to 240 V |
| Thailand | A, B, C, F | 220 V | 50 Hz | Yes | 220 to 240 V |
| Vietnam | A, C, F | 220 V | 50 Hz | Yes | 220 to 240 V |
| Singapore | C, G, M | 230 V | 50 Hz | No | 220 to 240 V |
| China | A, C, I | 220 V | 50 Hz | Yes | 220 to 240 V |
| South Korea | C, F | 220 V | 60 Hz | No | 220 to 240 V |
| Japan | A, B | 100 V | 50 Hz, 60 Hz | Yes | 100 to 127 V |
| Philippines | A, B, C | 220 V | 60 Hz | Yes | 220 to 240 V |
| Australia | I | 240 V | 50 Hz | No | 220 to 240 V |
| New Zealand | I | 230 V | 50 Hz | No | 220 to 240 V |
Of the 35 places, 8 run at 100 to 127 V like the US and 26 at 220 to 240 V. 12 besides the US list a Type A or B socket, but that only means the plug fits. In Thailand, China, Vietnam, Peru and the Philippines the socket may take a US plug while delivering 220 V. Brazil lists both 127 V and 220 V; the IEC notes that most states use 127 V, some use 220 V, and that the wrong voltage can destroy an appliance, so check the local voltage before plugging in. Japan runs at 100 V nationwide, with 50 Hz in the east and 60 Hz in the west, including Nagoya, Kyoto and Osaka.
One detail for Japan: on many US plugs the neutral pin is wider than the live pin. The IEC notes that Japanese plugs work in US sockets but often not the other way round, so a simple adapter can help even there.
One plug for most of the list
According to the IEC, a Type C plug fits not only Type C sockets but also E, F, J, K and N sockets. Checked against the table, a Type C plug or adapter has a matching socket in 22 of the 35 destinations. The ones where it does not: United States, Canada, Mexico, Bahamas, Dominican Republic, Costa Rica, Colombia, United Kingdom, Ireland, United Arab Emirates, Japan, Australia, New Zealand. Those list only Types A, B, D, G or I, and need their own adapter. Keep the 2.5 amp limit of Type C in mind (see below): it is a plug for chargers, not for heaters.
Frequency splits the list differently. 11 of the destinations run at 60 Hz, 23 at 50 Hz, and Japan at both, depending on the region. A device label that reads 50/60Hz covers both; a device rated for 60Hz only was made for 60 Hz power, like North America's.
Adapter or converter
- A plug adapter changes only the shape. A US plug goes in one side, the other side fits the local socket, and the voltage on the pins is whatever the country delivers.
- A voltage converter or step-down transformer changes the voltage, for example from 230 V to 120 V for an appliance that only works on 120 V. Japan's tourism board points travelers to a step-down transformer for appliances that are not dual voltage.
Which one you need is printed on the device. Look for the input line on the charger or the rating label: INPUT 100-240V ~ 50/60Hz means the maker rates it for every voltage and both frequencies in this table, so an adapter is enough. A label with a single value such as 120V 60Hz means the device is built for North American power only.
The math: current, power and what goes wrong
Power is voltage times current, so the current a device draws is its wattage divided by the voltage. The same device draws about half the current at 230 V as at 120 V:
| Device | Watts | Amps at 120 V | Amps at 230 V |
|---|---|---|---|
| Phone charger | 20 W | 0.17 A | 0.09 A |
| Laptop charger | 65 W | 0.54 A | 0.28 A |
| Hair dryer | 1,875 W | 15.6 A | 8.2 A |
A dual-voltage charger adjusts to this by itself. A 120 V-only heating appliance cannot. Treat a hair dryer as a heating element with a fixed resistance, the usual simplification, and its power grows with the square of the voltage: (230 ÷ 120)² = 3.67. A 1,875 W dryer plugged into 230 V through a plain adapter would try to draw about 6,888 W, far beyond what it was built for. That is why the adapter alone is the wrong fix for it, and why a converter must be rated above the device's wattage.
The plug itself has limits too. The IEC says Type C plugs are generally limited to 2.5 amps, which at 230 V is 575 W: enough for a charger, not for a kettle. A UK Type G plug carries a fuse, usually 3 amps for small appliances, 690 W at 230 V, or 13 amps for heavy ones, 2,990 W. The power converter turns watts into kilowatts, horsepower or BTU per hour, and volts, amps and watts explained covers the formulas in more depth.
Before you pack
- Find your destination in the table and note the plug types and the voltage group.
- Read the input line on every charger and appliance. 100-240V needs only an adapter.
- Leave single-voltage heating appliances at home when traveling from a 120 V country to a 220 to 240 V country, or use a converter rated above their wattage.
- For Brazil, ask the hotel which voltage the room has.
The rest of the trip runs on local money: the currency converter uses the daily reference rates, and tipping customs by country covers what to leave at a restaurant.
Frequently asked questions
What is the difference between a plug adapter and a voltage converter?
An adapter only changes the shape of the plug so it fits the socket; the voltage that comes out is still the local one. A converter or step-down transformer changes the voltage, for example from 230 V to the 120 V a US-only appliance expects. A charger marked 100-240V accepts both and needs only an adapter.
Which countries use the same plugs as the US?
In the IEC list, Canada, Mexico, Costa Rica, the Dominican Republic and the Bahamas use Types A and B at 110 to 127 V, like the US. Japan also uses Types A and B, at 100 V. Several countries with 220 V, such as Thailand, the Philippines and Peru, list Type A or B sockets too, so the plug fits but the voltage is double.
Will my US plug fit in Japan?
Usually, but not always. Japanese Type A sockets take two flat pins, but on US plugs the neutral pin is often wider than the live pin, and the IEC notes that Japanese plugs work in the US but often not the other way round. Japan runs at 100 V nationwide, with 50 Hz in the east and 60 Hz in the west.
What does 100-240V on a charger mean?
It is the range of input voltages the device is rated for. A charger marked 100-240V and 50/60Hz is made for the low-voltage and the high-voltage countries alike, so a plug adapter is enough. A device marked only 120V is not, and needs a converter rated above its wattage, or should stay at home.
Why does the UK plug have a fuse?
The Type G plug has a fuse built in, typically 3 amps for small appliances such as a computer and 13 amps for heavy ones such as heaters, according to the IEC. British sockets also have shutters on the live and neutral contacts so that objects cannot be pushed in.
Sources
- IEC World Plugs, list by location (plug types, electric potential and frequency for each country and territory; archived copy of November 2020)
- IEC World Plugs (the interactive guide is no longer available on the IEC site)
- IEC World Plugs, Type A (two flat parallel pins; US neutral pin wider than live pin; Japanese plugs fit US sockets but often not the other way round; archived)
- IEC World Plugs, Type C (Europlug with two round pins; fits E, F, J, K and N sockets; generally limited to 2.5 amps; archived)
- IEC World Plugs, Type G (three rectangular blades; built-in fuse, usually 3 or 13 amps; shuttered sockets; archived)
- IEC World Plugs, Type N (Brazil; most states 127 V, some 220 V; many appliances sold in Brazil are dual voltage; wrong voltage can destroy an appliance; archived)
- Japan National Tourism Organization: Plug and electricity (100 volts AC throughout Japan; 50 Hz in the east and 60 Hz in the west; dual-voltage devices work; a step-down transformer for other appliances)
General information based on the sources above, not tax, legal or financial advice.