Last updated October 8, 2026 · Report an error
An object simply dropped from a height — no throw, no launch angle — follows the simplest case of motion under gravity, but working out exactly how long it falls and how fast it's moving on impact still takes the right formulas. This calculator finds the fall time and impact velocity of an object dropped from rest at a given height, with a full step-by-step solution.
How it works
Enter the height the object falls from. The calculator applies the standard free-fall time formula (derived from the kinematics of constant acceleration) to find the fall time, then multiplies by gravitational acceleration to find the impact velocity.
- Enter height (m).
- Click Calculate to see your results.
Examples
An object dropped from 20 meters
This falls for about 2.02 seconds and hits the ground at approximately 19.81 m/s.
Who should use it
- Solving physics homework or exam problems involving objects dropped from a height.
- Estimating fall time and impact speed for a safety or engineering scenario.
Industry applications
- Physics and engineering education
- Safety engineering (fall hazard analysis)
Advantages
- Uses the exact standard free-fall kinematics formulas.
- Reports both fall time and impact velocity together.
Limitations
- Does not account for air resistance, which affects real-world accuracy, especially for lighter objects or greater heights.
Common mistakes to avoid
- Applying this formula to an object that was thrown or given an initial velocity, rather than simply dropped from rest.
- Ignoring that real-world air resistance can significantly reduce actual fall time and impact velocity compared to the ideal calculation, especially for light or high-drag objects.
Best practices
- Treat the result as an idealized upper bound on impact velocity — real falling objects (especially lightweight ones) will hit somewhat slower due to air resistance.
Tips
- Pair this with the Potential Energy Calculator to see how the object's potential energy at the starting height converts into kinetic energy by the time it lands.