# Doesn’t mass and weight measure the same thing?

Yes and no but, Not really

Mass is a measurement of the amount of matter something contains, while Weight is a force of the gravitational attraction the object feels towards another object like the Earth’s center
Mass is measured by using a balance comparing a known amount of matter to an unknown amount of matter. Weight is measured on a scale. The Mass of an object doesn't change when an object's location changes.

Weight, on the other hand, does change with location.
The mass of an object is a measure of the number of atoms in it.
The SI unit for mass is the kilogram.
The kilogram was originally defined in 1795 as the mass of one liter of water.
If you use the imperial system the unit is a slug which has a mass of 32.1740 lb
So if you weigh 161 pounds your mass is 5 slugs.

Weight is a measure of the force that gravity is pulling on an object.
Gravity is a force and therefore weight technically should be measured in newtons. A newton N  is equal to an acceleration of one kilogram one meter per second squared
For example, an object with a mass of one kilogram has a weight of about 9.8 newtons on the surface of the Earth
But here is where it may get confusing. There are other units that are used to describe weight that sound like mass.
The imperial system may use pounds to measure weight which is defined in terms of the kilogram as being exactly 0.45359237 kilograms.

Your weight can change based on the gravitational pull.
You weigh varies on the moon and other planets but your mass remains the same
If a cube has a mass of 90.91 kilograms and a weight of 200 pounds on Earth
It will weigh 33 pounds on the moon but still have a mass of 90.91 kilograms
On Mars, the cube would weigh 76 pounds but still have a mass of 90.91 kilograms
On Jupiter, the cube weighs 468 pounds and have a mass of 90.91 kilograms

So in conclusion,
Mass is a measure of how much matter something contains, which equals the number of atoms in it.
Weight is a measure of how strongly gravity pulls on something

The SI unit for mass in kilograms
The SI unit for weight is the newton N.
For example, an object with a mass of one kilogram has a weight of about 9.8 newtons on the surface of the Earth, and about one-sixth as much on the Moon.