Africa is the second-largest of the Earth's seven continents. With its adjacent islands, it covers about 30,330,000 km² (11,699,000 sq mi), or about 22% of the world's total land area. About 18% of the world's population lives in Africa.

Straddling the equator, Africa stretches 8,050 km (4,970 mi) from its northernmost point, Cape Blanc (Ra's al Abyad) in Tunisia, to its southernmost tip, Cape Agulhas in South Africa. The maximum width of the continent, measured from the tip of Cape Vert in Senegal, in the west, to Raas Xaafuun (Ras Hafun) in Somalia, in the east, is about 7,560 km (4,700 mi).

The highest point on the continent is the perpetually snowcapped Mount Kilimanjaro (5,895 m / 19,340 ft) in Tanzania; the lowest is Lake Assal, (153 m / 502 ft below sea level) in Djibouti.

Africa has a regular coastline characterized by few indentations. Its total length is only about 30,490 km (18,950 mi) and in proportion to its area is less than that of any other continent.

The main islands associated with Africa, which have a combined area of some 621,600 km² (240,000 sq mi), are Madagascar, Zanzibar, Pemba, Mauritius, Réunion, the Seychelles and the Comoro Islands in the Indian Ocean; São Tomé, Príncipe and Bioko in the Gulf of Guinea; St. Helena, Ascension, and the Bijagós Islands in the Atlantic; and the Cape Verde Islands, the Canary Islands and the Madeira Islands in the North Atlantic.

Although considered geographically part of Africa, St. Helena, Ascension, the Bijagós Islands, the Canary Islands and the Madeira Islands have few, if any, economic, political, or cultural links with the continent. Their ties are rather with Western Europe: St. Helena and Ascension are dependencies of the United Kingdom; the Canary and Madeira islands are an integral part of metropolitan Spain and Portugal respectively.

Countries in Africa are