Science · FACT #20
Ice is about nine percent less dense than liquid water.
The USGS says freezing decreases water’s density by about 9 percent, which makes ice less dense than liquid water and causes it to float.
Source: U.S. Geological Survey
https://www.usgs.gov/water-science-school/science/water-density
https://www.usgs.gov/water-science-school/science/water-density