Why is my weight different on the Moon?

Your mass is unchanged, but lunar gravity is much lower, so the weight force is smaller.

What distance should I enter for two bodies?

Use the distance between centers of mass, not the gap between surfaces.

Apparent weight can be zero in free fall or orbit, even though gravity still acts.

Calculate weight from mass and gravity, gravitational force between two bodies, or local gravity at altitude.

Calculation mode

Weight from mass and gravity Two-body gravitational force Gravity by body and altitude

Body mass

Celestial body

Custom gravitational acceleration

Weight force

686.5

Mass: 70 kg; gravity: 9.807 m/s²; force: 686.5 N

Everyday weight equivalent: ≈ 70 kgf

Weight force for mass 70 kg on different celestial bodies

Body	g, m/s²	Force, N	Equivalent, kgf
☀️ Sun	274	19,180	1,955.8
☿️ Mercury	3.7	259	26.411
🟠 Venus	8.9	623	63.528
🌍 Earth	9.80665	686.5	70
🌕 Moon	1.624	113.7	11.592
🔴 Mars	3.7	259	26.411
🟤 Jupiter	23.1	1,617	164.9
🪐 Saturn	9	630	64.242
🌀 Uranus	8.7	609	62.101
🔵 Neptune	11	770	78.518
🟣 Pluto	0.7	49	4.997

Gas giants have no solid surface: reference g values are tied to a conventional level in the atmosphere.

For English users, this page should answer both classroom weight-force questions and general gravity force questions.

W = m g

W is weight force, m mass and g local gravitational acceleration.

F = G \frac{m _{1} m _{2}}{r ^{2}}

r is the distance between centers of mass.

Mass vs weight

Mass stays the same when gravity changes. Weight is a force and changes with local gravitational acceleration.

Calculations are based on the listed reference sources. Links open in a new tab.

Updated: June 2, 2026

Solve Newton's second law for force, mass or acceleration with SI and imperial force units.

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