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How much of Earth’s surface is covered by oceans and marginal seas?

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Map graphic showing the boundaries of the five oceans-Pacific, Atlantic, Indian, Arctic, and Southern-using color-coded regions. Four different map projections are included: North Pole view, South Pole view, International Date Line view, and Greenwich Meridian view, each displaying the oceans' extents around the continents. — ocean Earth's oceans and their marginal seas cover nearly 71 percent of the planet's surface.

Oceans and their associated marginal seas cover approximately 70.8% to 71% of Earth’s surface.123

The remaining 29.2% of the planet's surface consists of land above sea level. This distribution is often illustrated through a hypsometric curve, which maps the elevation and depth of Earth's features relative to its total surface area. While oceans are defined as vast, continuous bodies of saltwater, marginal seas are typically smaller, shallower, and partially enclosed by land, often situated along the edges of the major ocean basins.13