What is a microgram?
A microgram is one millionth of a gram, written μg. Doses of some vitamins and medicines are measured in micrograms, and a grain of table salt weighs roughly 60μg.
What is a stone?
A stone is 14 pounds, or about 6.35 kilograms, and the United Kingdom and Ireland use it almost entirely for body weight. Elsewhere people use kilograms or pounds.
We provide a calculator on this site to convert stones to kilograms.