The weight of 1 liter of water is 1 kilogram. Volume of water is measured in liters, while the weight of solids is generally measured in kilograms. Water is often stored in containers, and the capacity of a container is always mentioned in liters.
Every liter is equal to 1,000 milliliters. One milliliter is also equal to 1,000 cubic centimeters. Hence, 1 milliliter is equal to 1 cubic centimeter. One cubic centimeter is also equal to 1 gram. Thus, every milliliter or every cubic centimeter of water weighs 1 gram. This works out to 1,000 grams for 1,000 milliliters of water. Thus, a liter of water weighs exactly 1 kilogram.