Free Fall Calculator
Calculate free-fall distance, velocity, and time under gravity with h = ½gt² and v = gt, using g = 9.80665 m/s². Enter any one value to find the rest.
Time to fall
2.01962 s
Distance fallen
20 m
Impact velocity
19.8057 m/s
Free fall from rest: h = ½·g·t², v = g·t. Air resistance is ignored. g = 9.80665 m/s² on Earth.
Frequently Asked Questions
What are the free-fall equations?
For an object dropped from rest (ignoring air resistance), the distance fallen is h = ½·g·t² and the velocity is v = g·t, where g = 9.80665 m/s² is the gravitational acceleration. Time to fall a height h is t = √(2h / g).
How do I calculate the time to fall a given height?
Use t = √(2h / g). For example, falling 20 m takes √(2 × 20 / 9.80665) ≈ 2.02 seconds.
How fast is an object going after falling for some time?
Use v = g·t. After 3 seconds of free fall, the speed is 9.80665 × 3 ≈ 29.4 m/s, assuming no air resistance.
Does mass affect free fall?
No. In the absence of air resistance, all objects fall with the same acceleration g regardless of mass — this is why a feather and a hammer fall together in a vacuum.
What is the value of g used here?
This calculator uses standard gravity, g = 9.80665 m/s², the internationally accepted average for Earth's surface. You can adjust it for other planets.