What is mass?

Mass is a measure of how much stuff, or matter, is in an object. It is measured in grams (g) and kilograms (kg) using scales or a balance. In everyday life mass is often called weight, though weight is really the pull of gravity on that mass.

Examples

• An apple has a mass of about 100 g.
• A bag of sugar is often 1 kg.
• 1 kilogram = 1000 grams.

Quick facts

• 1 kilogram is the same as 1000 grams.
• Mass stays the same wherever you are; weight changes with gravity.