The Indian Ocean is the third largest of the world's oceans, covering approximately 20% of the water on the Earth's surface.
It is bounded on the north by the Indian subcontinent; on the west by East Africa; on the east by Indochina, the Sunda Islands, and Australia; and in the far-south by the Southern Ocean.
The Indian Ocean is nearly 10,000 kilometres (6,200 mi) wide at the southern tips of Africa and Australia; its area is 73,556,000 square kilometres (28,350,000 sq mi), which includes the Red Sea and the Persian Gulf.
The ocean's volume is estimated to be 292,131,000 cubic kilometres. Island nations within the ocean are Madagascar, the world's fourth largest island; Reunion Island; Comoros; Seychelles; Maldives Mauritius; and Sri Lanka. The archipelago of Indonesia borders the ocean in the east.
The average depth of the Indian Ocean is measured at 3,890 m (12,762 ft). Its deepest point is the Diamantina Deep in Diamantina Trench, at 8,047 m (26,401 ft) deep.