Frequently Asked Questions

Enter your weight on Earth and the tool multiplies it by each body's surface-gravity ratio, showing what you'd weigh across the chosen planetary system — no button refresh needed. Switch between Our Solar System and the TRAPPIST-1 System using the tabs above the results; your entered weight and chosen unit are preserved when you switch.

Yes, it's completely free with no sign-up, downloads, or limits. Calculate as many weights as you like, as often as you like.

Yes. Switch to the TRAPPIST-1 System tab to see your weight on seven real exoplanets orbiting another star about 39 light-years from Earth, in the constellation Aquarius. TRAPPIST-1 is an ultracool dwarf star — much smaller and cooler than our Sun — and its planets are the most precisely measured exoplanets known.

Surface gravity depends on a planet's mass and radius (g ∝ M/R²). The TRAPPIST-1 planets are included precisely because both have been measured well — mass via transit timing variations, and radius via transit photometry. Only bodies with both measurements are listed. Worlds known only by minimum mass or only by radius are excluded because gravity can't be reliably computed without both. The values shown are best estimates from current measurements and carry inherent uncertainty, as noted in the tool.

Your mass — the amount of matter in you — stays constant everywhere in the universe. Weight is the force that gravity exerts on that mass, so it varies depending on each world's gravitational pull. On the Moon, gravity is only about 16.5% of Earth's, so you'd feel much lighter even though you're exactly the same person carrying exactly the same matter.

In Our Solar System: all eight planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune) plus the Moon, the Sun, and Pluto — eleven bodies in total. Earth is shown as your reference point so you can confirm your input before comparing. In the TRAPPIST-1 System: planets b, c, d, e, f, g, and h.

Yes. Enter and view your weight in kilograms, pounds, or stone, and every result updates instantly in your chosen unit. Switching units also auto-converts your input value — so you never have to re-type your weight. The same conversion applies when viewing either planetary system.

In the Solar System you'd weigh most on the Sun (about 27.9× your Earth weight), then Jupiter at about 2.36×. You'd weigh least on Pluto (just 6.3% of Earth weight) and the Moon (16.5%). In the TRAPPIST-1 System, TRAPPIST-1 e has gravity closest to Earth's (~0.91×), making it the most Earth-like, while TRAPPIST-1 d is the lightest at ~0.48×.

No. Your weight is processed directly in your browser and is never stored or sent to a server, keeping your information completely private. Close the tab and everything is gone.

Not really. Gas giants and the Sun have no solid surface, and several TRAPPIST-1 planets may be tidally locked, frozen, or wrapped in thick atmospheres — none are places a person could comfortably stand. The figures are a fun, hypothetical comparison of gravitational pull, not a survivable scenario. Think of it as a thought experiment in physics.