Weight Calculator

Mass is the amount of matter in an object and remains constant regardless of location — it's measured in kilograms (kg). Weight is the force exerted on that mass by gravity, measured in Newtons (N). Your mass stays the same whether you're on Earth or the Moon, but your weight changes because gravity differs.

Weight is calculated using the formula W = m × g, where W is weight in Newtons, m is mass in kilograms, and g is gravitational acceleration in m/s². On Earth, g ≈ 9.807 m/s², so a 70 kg person weighs approximately 686.5 N.

The Moon's gravitational acceleration is only about 1.62 m/s², roughly one-sixth of Earth's 9.807 m/s². Because weight equals mass multiplied by gravity, a lower gravitational pull produces a lower weight force — even though your mass is unchanged.

In the scientific (SI) system, weight is measured in Newtons (N). In everyday usage, people often confuse weight with mass and quote it in kilograms or pounds. The pound-force (lbf) is the imperial unit of force/weight, where 1 lbf ≈ 4.448 N.

Simply select 'Pounds (lbs)' from the Mass Unit dropdown — the calculator automatically converts your value to kilograms before computing weight. One pound equals approximately 0.4536 kg.

The standard gravitational acceleration on Earth is defined as 9.80665 m/s² (often rounded to 9.807 or 9.81). This value can vary slightly depending on altitude and latitude — it's slightly lower at the equator and higher at the poles.

Yes. Select 'Custom Gravity' from the Gravity Location dropdown and enter any gravitational acceleration value in m/s². This is useful for engineering calculations, physics problems, or simulating weight on hypothetical planets or environments.

Jupiter has a gravitational acceleration of approximately 24.79 m/s², about 2.53 times that of Earth. A person with a mass of 70 kg would weigh around 1,735 N on Jupiter, compared to about 686 N on Earth. You can use the planetary comparison table in this calculator to see all values at once.