The primary unit for measuring weight is the kilogram (kg) in the International System of Units (SI). Weight is defined as the force exerted by gravity on an object’s mass, and it is measured in newtons (N) in scientific contexts. However, when referencing weight in everyday situations, kilograms are commonly used to indicate the mass of an object. One kilogram is equivalent to the weight of an object under one standard gravity (9.81 m/s²). Thus, while kilograms measure mass, they are frequently used to represent weight in practical applications.