What is the difference between mass and weight?

Mass is the amount of matter in an object (constant everywhere). Weight is the force of gravity on that object (varies by planet).

Why do I weigh less on the Moon?

The Moon has weaker gravity (approx 1/6th of Earth's), so it pulls on your mass with less force.

Since weight is a force, its SI unit is Newtons (N). In common parlance, we often confuse kg/lbs (mass) with weight.

Calculate your weight on different planets.

Mass (m)

Location / Planet

Custom Gravity (Optional)

m/s²

Weight on Earth

—N

Mass remains 70 kg

Physics Formulas

Weight

Gravity

Frequently Asked Questions

How to Use

What it calculates

This weight & mass computes physics quantities using established scientific equations. Weight on different planets.

When to use it

Use for coursework, lab work, and engineering estimates where quick accurate results are needed.

Example

Adjust the inputs above to model your specific scenario with the Weight & Mass.

Explore More

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Rotational force (moment).

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Velocity and position under gravity.