Which percentage of the Earth’s water is fresh water?

Water covers about 71% of the earth's surface and Only 3% is fresh water, where 97% of the earth's water is found in the oceans (too salty for drinking, growing crops, and most industrial uses except cooling).

2.5% of the earth's fresh water is unavailable for many reasons such as: locked up in glaciers, polar ice caps, atmosphere, and soil; or highly polluted; or lies too far under the earth's surface to be extracted at an affordable cost. So technically 0.5% of the earth's water is available fresh water.

If the world's water supply were only 100 liters (26 gallons), our usable water supply of fresh water would be only about 0.003 liter (one-half teaspoon). In actuality, that amounts to an average of 8.4 million liters (2.2 million gallons) for each person on earth. This supply is continually collected, purified, and distributed in the natural hydrologic (water) cycle.