A 70 kg person would weigh about 26 kg on Mars, 165 kg on Jupiter, and a knee-buckling 1,953 kg standing on the surface of the Sun, if the Sun had one. None of that means you'd actually be heavier or lighter as a person. It means the planet under your feet is pulling on you with a different amount of force, and this calculator just runs that ratio for every major body in the solar system at once.
Mass Isn't Weight, and That's the Whole Trick
Your mass, roughly speaking, is how much matter you're made of. It doesn't change whether you're standing in your kitchen or floating outside the International Space Station. Weight is different: it's the force gravity exerts on that mass, and gravity depends entirely on the size and density of whatever you're standing on. Step onto a smaller, less dense world and gravity pulls less hard, so a bathroom scale under your feet would read a smaller number, even though you, the actual physical amount of you, haven't changed at all.
That distinction is why astronauts can be seen bounding across the Moon in giant leaps while wearing a suit and equipment that would be exhausting to carry on Earth. Their mass, suit included, is identical in both places. Their weight on the Moon is roughly a sixth of what it is at home, because lunar gravity is roughly a sixth of Earth's.
The Formula Behind Every Number on This Page
Every result here comes from one simple ratio: your weight on another body equals your Earth weight multiplied by that body's surface gravity, expressed as a multiple of Earth's. Mars sits at 0.377, meaning its gravity is a bit over a third of Earth's, so multiplying your weight by 0.377 gives your Mars weight directly. Jupiter sits at 2.36, more than double Earth's pull, which is why it dominates the list even though it's a gas giant with no ground to actually stand on.
These gravity ratios themselves come from a body's mass and radius, since surface gravity is proportional to mass divided by radius squared. A planet can be more massive than Earth and still have weaker surface gravity if it's also proportionally larger, which is part of why the ranking of planets by mass and the ranking by surface gravity don't match up perfectly.
A Quick Tour of the Solar System, by Gravity
Mercury and Mars are surprisingly similar despite one being scorched and airless and the other cold and thin-aired: both sit at roughly 0.38 times Earth's gravity, so you'd weigh almost the same on either. Venus is the closest match to Earth in the entire solar system at 0.907, close enough that a 70 kg person would weigh about 63.5 kg there, a genuinely modest difference compared to everywhere else on this list. The Moon, at 0.166, is the most dramatic reduction among nearby bodies, which is exactly why lunar footage looks the way it does.
On the heavier end, Neptune edges out Earth slightly at 1.12, meaning you'd weigh a touch more there than at home despite Neptune being nearly four times Earth's diameter, a direct result of its lower density spreading that mass across a much bigger radius. Saturn, despite being the second-largest planet in the solar system, comes in at 0.916, just under Earth's own gravity, for the same density-and-radius reason. Uranus lands close by at 0.889. Pluto, reclassified as a dwarf planet in 2006 but still worth including for scale, sits at just 0.071, meaning a 70 kg person would weigh under 5 kg there.
Why Gas Giants Don't Actually Have a "Surface"
Jupiter, Saturn, Uranus, and Neptune don't have solid ground the way Earth or Mars does, they're balls of hydrogen and helium (with Uranus and Neptune carrying more ice and heavier compounds) that get denser with depth without ever hitting a hard boundary. When NASA and other space agencies publish a "surface gravity" figure for these planets, they're actually reporting gravity at the 1-bar pressure level, roughly the altitude where atmospheric pressure matches sea-level pressure on Earth, used as a consistent reference point purely for comparison. The Sun's figure works the same way, measured at the photosphere, the visible "surface" layer you'd see if you looked at it (please don't, even briefly, with unprotected eyes) rather than any solid boundary, since the Sun is plasma all the way through.
A Worked Example
Take a 70 kg person. On Mercury (0.378), that's 26.5 kg. On Venus (0.907), 63.5 kg. On Mars (0.377), 26.4 kg, almost identical to Mercury. On Jupiter (2.36), 165.2 kg, more than double their Earth weight. On Saturn (0.916), 64.1 kg. On Uranus (0.889), 62.2 kg. On Neptune (1.12), 78.4 kg, the only planet where they'd weigh meaningfully more than on Earth. On Pluto (0.071), just 5 kg. And on the Sun (27.9), a genuinely physics-breaking 1,953 kg, nearly two metric tons, which no human body or spacecraft could survive standing anywhere near, given the Sun's surface temperature and the fact that it has no solid surface to begin with. If a scaled-down version of that kind of force is the part you find interesting, the Meteor Impact Calculator covers the other end of solar-system physics: the energy released when something falls toward a planet instead of standing on one.
How to Use This Calculator
Enter your weight in kilograms or pounds and the full list updates instantly for every major body, sorted in solar system order from Mercury out to Pluto, with the Moon slotted in next to Earth and the Sun called out at the end for scale. Nothing is stored or sent anywhere, the math runs entirely in your browser.
Frequently Asked Questions
Why would I weigh more on Neptune if it's not even that dense?+
Surface gravity depends on both mass and radius. Neptune is far less dense than Earth, but it's also nearly four times wider, and that extra mass spread across a much larger sphere still adds up to slightly stronger gravity at its reference altitude than Earth's.
Does my actual body mass change on another planet?+
No. Mass is constant regardless of location. Only weight, the force gravity applies to that mass, changes from body to body.
Why isn't Jupiter's gravity ratio higher, given how massive it is?+
Jupiter is roughly 318 times Earth's mass, but it's also about 11 times wider, and surface gravity falls off with the square of radius. That radius advantage cancels out most of the mass advantage, leaving Jupiter at 2.36 times Earth's gravity rather than something in the hundreds.
What gravity figure does this use for the gas giants and the Sun?+
The standard reference-level figures NASA itself publishes: the 1-bar pressure level for Jupiter, Saturn, Uranus, and Neptune, and the visible photosphere for the Sun, since none of them have a solid surface to measure from directly.
Is Pluto included even though it's not a full planet anymore?+
Yes, purely for scale and because people still ask about it. The International Astronomical Union reclassified Pluto as a dwarf planet in 2006, but its published surface gravity figure is well established and worth including here.
Same you, different pull.
Nothing about you changes from planet to planet, just how hard the ground under your feet is pulling back. The ratio is the entire story, and now you've got it for every major body in the solar system at once.
Try Jupiter first. It's the most dramatic number on the list.
Sources and References
- NASA. Planetary Fact Sheet. nssdc.gsfc.nasa.gov. Accessed August 2026.
- International Astronomical Union. IAU 2006 General Assembly: Result of the IAU Resolution Votes. iau.org. Accessed August 2026.