What Is the Difference Between Weight and Mass?

Mass vs Weight: Comparing and Understanding the Differences

The difference between mass and weight is that weight reflects how gravity pulls on an object.
The difference between mass and weight is that weight reflects how gravity pulls on an object. On Earth, the values for mass and weight are the same. artpartner-images, Getty Images

The terms "mass" and "weight" are used interchangeably in ordinary conversation, but the two words don't mean the same thing. The difference between mass and weight is that mass is the amount of matter in a material while weight is a measure of how the force of gravity acts upon that mass.

Mass is the measure of the amount of matter in a body. Mass is denoted using m or M.

Weight is the measure of the amount of force acting on a mass due to the acceleration due to gravity.

Weight usually is denoted by W. Weight is mass multiplied by the acceleration of gravity.

W = m * g

Comparing Mass Versus Weight

Here's a table the compares the differences between mass and weight. For the most part, if you're on Earth and not moving, the values for mass and weight will be the same. If you change your location with respect to gravity, mass will remain unchanged, but weight will not. For example, your body's mass is a set value, but your weight is different on the Moon compared with on Earth.

Comparison of Mass and Weight
Mass is a property of matter. The mass of an object is the same everywhere,Weight depends on the effect of gravity. Weight varies according to location.
Mass can never be zero.Weight can be zero if no gravity acts upon an object, as in space.
Mass does not change according to location.Weight increases or decreases with higher or lower gravity.
Mass is a scalar quantity. It has magnitude.Weight is a vector quantity. It has magnitude and is directed toward the center of the Earth or other gravity well.
Mass may be measured using an ordinary balance.Weight is measured using a spring balance.
Mass usually is measured in grams and kilograms.Weight often is measured in newtons, a unit of force.