The standard unit of measurement for mass is a gram, as designated by the International System of Units (SI). While many industries continue to measure mass in ounces, pounds and tons in the United States, metric measurements are used in science, medicine and technical fields.
The base unit for measuring mass is very small, and an example of an item with a mass of 1 gram is a standard paperclip. In science, a gram is equivalent to a cubic centimeter of water. Larger items are measured in kilograms, quintals and metric tons. A kilogram is equivalent to 1,000 grams. A quintal is equivalent to 100 kilograms, and a metric ton is equivalent to 1,000 kilograms.