Official Language

An official language is one designated by a country for use in government, law, education, and judicial proceedings. While many countries have one official language, Switzerland has 4 (German, French, Italian, Romansh) and Singapore has 4 (English, Chinese, Malay, Tamil).

English is official in about 60 countries, French in 29, and Arabic in 26. Many African countries retain their former colonial power's language (English, French, Portuguese) as official.

Language is a powerful filter. 'Portuguese official language' limits to 9 countries. 'Thai official language' means Thailand alone. Less common languages have fewer candidate countries, making minor language knowledge especially valuable.