Falling Object Time Calculator

How long would it take to hit the ground — on any world?

Drop something from a given height and see exactly how long it takes to land — and how fast it's moving on impact — on every planet, the Moon, Pluto and the Sun, using the real free-fall formula t = √(2h/g). See why Apollo 15's hammer and feather landed on the Moon at the exact same instant, and how much longer (or faster) the same drop plays out on other worlds. Runs fully in your browser — nothing is uploaded.

About Falling Object Time Calculator

Falling Object Time Calculator features

How to use Falling Object Time Calculator

  1. Enter a drop height

    Type how far the object falls, in metres or feet — 100 m (about a 30-storey building) is the starting default.

  2. Scan the results

    Each card shows the same drop height applied to every planet, moon and the Sun, with the fall time and impact speed.

  3. Jump to a world

    Use the dropdown to scroll straight to Mars, Jupiter, the Moon or any other body.

  4. See the pattern

    Notice how much longer things take to fall on low-gravity worlds like the Moon, and how fast they slam down on giants like Jupiter.

Frequently asked questions

How do you calculate how long something takes to fall?

It comes down to just two things: how far it falls, and how strong that world's gravity is. Drop it from higher up and it takes longer; drop it somewhere with stronger gravity and it lands sooner. Want the exact maths? See the "How the formula works" section above — it walks through the real equation with a worked example.

Does a heavier object fall faster?

No — with no air in the way, everything falls at exactly the same rate no matter how heavy it is. This is famously shown by the Apollo 15 hammer-and-feather drop on the airless Moon: both landed at the same instant.

What was the Apollo 15 hammer and feather experiment?

In 1971, astronaut David Scott dropped a geologist's hammer and a falcon feather at the same time on the Moon's surface, live on camera. With no air to slow the feather down, both objects hit the ground at the exact same moment — proving, for real, an idea Galileo had predicted centuries earlier.

How long would it take to fall 100 metres on the Moon vs Earth?

On Earth, a 100 m fall takes about 4.5 seconds. On the Moon — with only about 1/6th of Earth's gravity — the same 100 m fall takes roughly 11 seconds, more than twice as long. Try entering 100 in the calculator above to see every world at once.

Does this calculator account for air resistance?

No — it assumes a clean drop with nothing slowing it down, the standard classroom-physics assumption. That's exactly right on airless worlds like the Moon, and a very close match on Earth for solid, compact objects falling normal heights. Very light or wide objects (feathers, parachutes) would fall slower in real Earth air than this calculator shows.

What is terminal velocity, and why isn't it included here?

It's the fastest speed a falling object can reach on Earth once air resistance pushes back just as hard as gravity pulls down — around 200 km/h for a skydiver. This calculator assumes no air at all, so on Earth, for very long drops of light objects, the real fall would actually take a bit longer than shown here.

Is this falling object time calculator free?

Yes — completely free, with no sign-up and no app to install. Every calculation runs instantly in your browser, and nothing you enter is stored or uploaded.

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