Which ocean is the largest by surface area?

The Pacific Ocean is the largest ocean by surface area, covering roughly 165 million square kilometres. It occupies about one-third of Earth’s total surface and is larger than all of Earth’s land area combined under commonly used geographic boundaries.

The Pacific stretches from the Arctic region in the north toward Antarctica in the south. Asia and Australia border it to the west, while North and South America form its eastern boundary. Its enormous basin contains thousands of islands and major marginal seas, including the Philippine Sea, the South China Sea, the Coral Sea, and the Sea of Japan.

The Pacific is also Earth’s deepest ocean. The Mariana Trench lies in its western basin, and Challenger Deep reaches nearly 11,000 metres below sea level. The name has an age-of-exploration origin: Vasco Núñez de Balboa saw the ocean from the Isthmus of Panama in 1513, while Ferdinand Magellan later called it “peaceful” after encountering relatively calm conditions during his voyage.

A common mistake is confusing size with depth or coastline length. The Atlantic is also vast, but the Pacific is larger in surface area and volume.