What's the biggest ocean in the world?

The biggest ocean in the world is the Pacific Ocean. It covers an area of approximately 63.8 million square miles (165.25 million square kilometers) and is the largest body of water on Earth, occupying about one-third of the planet's total surface area. The Pacific Ocean is also the deepest ocean, with an average depth of around 12,080 feet (3,682 meters) and a maximum depth of 36,070 feet (10,994 meters) in the Mariana Trench.