What is the specific gravity of water?

The specific gravity of water at 4 degrees Celsius is equal to 1 gram per cubic centimeter. Specific gravity is a measurement used to compare the density of an object with water at its densest point, which is at a temperature of 4 degrees Celsius.

Objects with a specific gravity of 1 gram per cubic centimeter or less will float in water at 4 degrees Celsius, while objects with a specific gravity greater than 1 gram per cubic centimeter sink in water of the same temperature. Specific gravity measurements of liquid are performed using a device known as a hydrometer.