About 71% of the Earth's surface is covered by water, primarily in the form of oceans
. In terms of total water volume on Earth, approximately 96.5% is salt water found in the oceans, while only about 3.5% is freshwater
. To clarify, when considering the entire Earth (including land and interior), water constitutes a small fraction of the planet's mass-about 0.02%-but it dominates the surface coverage
. The oceans hold the vast majority of Earth's water, with freshwater mostly locked in glaciers, ice caps, groundwater, and a small fraction available as surface water in lakes and rivers
. In summary:
- Water covers roughly 71% of Earth's surface.
- About 96.5% of Earth's water is salt water in oceans.
- Only about 3.5% of Earth's water is freshwater.
- Freshwater is mostly frozen or underground; only a small fraction is surface liquid freshwater accessible for human use
This distribution explains why Earth is often called the "Blue Planet" due to the extensive ocean coverage visible from space.