Would I really be lighter on the Moon?

You would weigh less — about one sixth of your Earth weight — but you would not have less body. Your mass, and everything it does for your health, is unchanged.

On which planet would I weigh the most?

Jupiter, the most massive planet, has the strongest surface gravity — you would weigh about two and a half times your Earth weight there.

Does my BMI change on another planet?

No. BMI uses mass and height, and neither changes with gravity. It is a fun thought experiment, not a real health metric off Earth.

Why do astronauts float if they still have weight?

In orbit they are in constant free fall around Earth, so they feel weightless even though gravity still acts on them. That is different from truly leaving gravity behind.

What Would You Weigh on Other Planets?

Published 2/27/2026 · 2 min read · Health calculators

Sofia Nunes — Health & wellness writer at Allin

Nutrition · Hydration

Checked against 2 sources

View profile →

In short

Your weight changes from planet to planet because it depends on gravity, while your mass — the amount of matter in you — stays the same. On the Moon you would weigh about one sixth of your Earth weight; someone who weighs 154 lb on Earth would weigh roughly 26 lb on the Moon and about 58 lb on Mars.

Weight depends on gravity, but mass does not — here is why you would weigh differently on the Moon, Mars and Jupiter, and how to work it out.

Weight versus mass

Mass is the amount of matter you are made of, and it does not change no matter where you are. Weight is the force that gravity pulls on that mass with, so it depends on where you stand. On a bathroom scale on Earth, the two feel like the same thing, but they are not — travel to another world and your mass is unchanged while your weight shifts.

Why gravity differs

Surface gravity depends on a planet's mass and radius. A more massive body pulls harder, but a larger radius spreads that pull, so the two effects compete. The Moon's surface gravity is about one sixth of Earth's, Mars is about 38%, and giant Jupiter would pull at roughly two and a half times Earth's gravity at its cloud tops.

How to calculate your planet weight

Multiply your Earth weight by the planet's surface-gravity ratio. If you weigh 154 lb, the Moon (0.166) gives about 26 lb, Mars (0.38) about 58 lb, and Jupiter (2.53) about 390 lb. Because it is a simple ratio, your BMI and body shape do not change — only the number the scale reads.

Worked with our own calculator

Weight on other planets calculator

Given

Your weight (kg): 63
Planet: Mercury

Result

Weight there (kg): 23.814

These figures are produced by the calculator below, not typed in by hand — they are recomputed whenever the tool changes.

Run it on your own figures →

Frequently asked questions

Would I really be lighter on the Moon?: You would weigh less — about one sixth of your Earth weight — but you would not have less body. Your mass, and everything it does for your health, is unchanged.
On which planet would I weigh the most?: Jupiter, the most massive planet, has the strongest surface gravity — you would weigh about two and a half times your Earth weight there.
Does my BMI change on another planet?: No. BMI uses mass and height, and neither changes with gravity. It is a fun thought experiment, not a real health metric off Earth.
Why do astronauts float if they still have weight?: In orbit they are in constant free fall around Earth, so they feel weightless even though gravity still acts on them. That is different from truly leaving gravity behind.

Articles you may find interesting

All guides →

How-toHow to Find Your Target Weight for a Healthy BMIThe healthy BMI band of 18.5–24.9 turns into a weight range once you know your height. Here is how to work out yours step by step.ExplainerWhat Is a Child Growth Percentile?Growth percentiles compare a child's height and weight to others the same age and sex. Here's how to read them and what really matters.ExplainerWhat Is a Healthy Waist-to-Height Ratio?Keeping your waist under half your height is a simple health marker. Learn what waist-to-height ratio means, how to measure, and why under 0.5 is the goal.ExplainerWhat Is a Healthy BMI?BMI groups weight into ranges relative to height. Here's what counts as healthy, how to calculate it, and the limits of the number.ExplainerWhat Is Your Ideal Weight?There's no single ideal weight — it's a healthy range. Here's what the common formulas say, what they miss, and better ways to judge a healthy weight.ExplainerWhat Is a Good Body Fat Percentage?Body fat percentage is a better health signal than weight alone. Here are the healthy ranges by sex, how it's measured, and how to use it wisely.

For general information only — not medical advice; consult a professional.

Sources

Spotted a mistake in this article?