What percent of Earth's water is fresh water?

• A. 1 percent
• B. 50 percent
• C. 10 percent
• D. 3 percent

Answer: (D)

Freshwater is a tiny portion of all the water on Earth. Most of our planet’s water sits as salty ocean water, not drinkable as is. Of the freshwater that exists, the majority is locked up in ice caps and glaciers, with the rest in groundwater and only a small amount in rivers, lakes, and other surface sources. Because of this distribution, the total amount of freshwater in the world is about 3 percent of all Earth's water (often rounded from a precise figure near 2.5%). That’s why the commonly cited answer is 3 percent. The other options are far off because they imply much larger shares of water are freshwater, which isn’t the case given the dominance of saltwater and the large fraction of freshwater stored in ice.