The Strait of Malacca is a narrow, funnel shaped 890 kilometre stretch of water that runs between the Malay Peninsula and extreme southern Thailand to the east, and the Indonesian island of Sumatra to the west. It has a surface area of 25,000 square kilometres, a width of 65 kilometres at its narrowest that widens to the north to 250 kilometres, and its shallowest depth is just 25 metres.

Strategically and economically, the Malacca Strait is one of the most vital shipping lanes in the world as it is the main shipping channel between the Indian Ocean and the Pacific Ocean, linking the major Asian economies of India, China, Japan, Taiwan, and South Korea. Approximately a quarter of the world’s traded goods, including products manufactured in China, and Indonesian coffee pass through here every year. Roughly 25% of all oil carried by sea also passes through the Strait, predominantly from suppliers in the Persian Gulf to Asian markets.

The Malacca Strait is also one of the world's most congested shipping choke points since it narrows to only 2.8 kilometres wide at the Phillips Channel which is close to the south of Singapore, and its shallow depth at some points means the larger ships cannot pass through and must detour several thousand kilometres to use the Lombok Strait, Makassar Strait, Sibutu Passage, or Mindoro Strait instead.