Planetary Weight

Your weight isn't actually a fixed property of your body — it's a measurement of how hard gravity is pulling on your mass. Your mass (the amount of matter in your body) stays the same everywhere in the universe, but your weight changes depending on the local gravitational field. That's why astronauts float on the International Space Station and why you'd feel dramatically lighter on the Moon and heavier on Jupiter.

This calculator uses the real, measured surface gravity of each planet relative to Earth's to convert your Earth weight into your weight on Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune, and the Moon. Jupiter's immense mass gives it more than double Earth's surface gravity, while Mars — thin and small — has only about 38% of Earth's pull. The Moon, with no atmosphere and a fraction of Earth's mass, sits at just under 17% of Earth gravity, which is why moonwalking footage shows astronauts bounding around so easily.

Enter your weight and instantly see the real physics play out across the solar system — accurate surface gravity ratios, not guesswork.

Like our companion Age on Other Planets tool, this calculator is grounded in real, verifiable physics rather than novelty math. Surface gravity — determined by a planet's mass and radius according to Newton's law of universal gravitation — is a precisely measured value for every major body in the solar system, published by NASA and used throughout aerospace engineering, mission planning, and astronomy education.

This makes the tool both fun and genuinely educational. It's a common classroom demonstration for teaching gravity, mass versus weight, and why astronaut training involves neutral buoyancy pools (to simulate reduced gravity) and why Mars rover engineers had to account for lower gravity when designing landing systems. Seeing your own weight recalculated across seven planets and the Moon makes an abstract physics concept immediately personal and memorable — which is exactly why this kind of calculator tends to get shared and revisited, unlike purely for-fun tools that carry no scientific weight of their own.