16 U.S. fluid ounces of water weighs 1.04 pounds at room temperature.
Despite the common saying that “a pint is a pound everywhere in the world” and the fact that 16 ounces equals 1 pint, the weight of a pint is not always exactly 1 pound.
Temperature influences the water’s density and specific gravity. When water is cold enough to freeze at 32 degrees Fahrenheit, its specific weight is 8.34 pounds per gallon, so 16 ounces of water weighs 1.05 pounds.
When water reaches its boiling point of 212 degrees Fahrenheit, its specific weight decreases to 8 pounds per gallon, so 16 ounces weigh 1 pound.