The world, coloured by what you would have to pack

Pick where you are travelling from. Every country then shows what it would take to use your own devices there — nothing, a plug adapter, an adapter that costs you the earth connection, or a converter. Answers come from the same rule engine as the trip checker on the front page.

• 100–127 V
• 220–240 V
• No supply figure
• Provisional

The 72 too small to draw

At the resolution this map is drawn, these are sub-pixel or absent — and several of them are the most useful rows in the dataset, because they diverge from the country around them. Hong Kong is Type G where mainland China is A, C and I; Puerto Rico runs the US supply. They are listed rather than dropped, and they recolour with the map.

• American Samoa
• Andorra
• Anguilla
• Antigua and Barbuda
• Aruba
• Bahrain
• Barbados
• Bermuda
• Bonaire, Sint Eustatius and Saba
• British Virgin Islands
• Cape Verde
• Cayman Islands
• Christmas Island
• Cocos (Keeling) Islands
• Comoros
• Cook Islands
• Curaçao
• Dominica
• Faroe Islands
• French Guiana
• French Polynesia
• Gibraltar
• Grenada
• Guadeloupe
• Guam
• Guernsey
• Hong Kong
• Isle of Man
• Jersey
• Kiribati
• Liechtenstein
• Luxembourg
• Macau
• Maldives
• Malta
• Marshall Islands
• Martinique
• Mauritius
• Mayotte
• Micronesia
• Monaco
• Montserrat
• Nauru
• Niue
• Norfolk Island
• Northern Mariana Islands
• Palau
• Palestine
• Pitcairn
• Réunion
• Saint Barthélemy
• Saint Helena
• Saint Kitts and Nevis
• Saint Lucia
• Saint Martin
• Saint Pierre and Miquelon
• Saint Vincent and the Grenadines
• Samoa
• San Marino
• Sao Tome and Principe
• Seychelles
• Singapore
• Sint Maarten
• Svalbard and Jan Mayen
• Tokelau
• Tonga
• Turks and Caicos Islands
• Tuvalu
• US Virgin Islands
• Vatican City
• Wallis and Futuna
• Åland Islands

What clicking does

With no origin chosen, every country goes to its own page — its supply, its sockets, and what fits them. Once you pick an origin, every country instead goes to the answer for that pair, with both ends already filled in: choose Ireland, click the United States, and you land on the packing list for Ireland to the United States rather than on a page about American sockets. The country you are travelling from keeps its own page, because "you are already there" is not an answer worth a click.

How this map is coloured

Five states, in order of how much they cost you, and no claim of distance between them. An earlier design coloured countries so that the perceptual distance between two colours stood for electrical incompatibility. It was withdrawn: a Type C plug enters a Type F socket and a Type F plug does not enter a Type C socket, so compatibility is directed and non-transitive, while colour distance is symmetric. No arrangement of hues can carry that relation, and one that appears to is worse than one that does not try.

With no origin chosen the map shows nominal supply voltage only, which is a plain category and asserts nothing about how far apart two countries are.

Fifteen countries have no voltage or socket list recorded at all. There is nothing to compute for them, so they are drawn in a neutral grey and claim nothing.

A further nineteen have a value that two references disagree about, or that only one of them carries. Those are coloured from the data as it stands and marked with a dashed edge, not greyed out. An earlier version withheld them, which lost the reader an answer we already had in order to express a caveat they could not act on. The marking comes off as rows are verified, and the country’s own page shows both references side by side.