Free Fall Time Calculator
Fall time and impact speed from height.
Enter your values
ⓘ Live results
Results
- Fall time
- 2.02 s
- Impact speed
- 19.81 m/s
- Impact speed
- 71.3 km/h
- Impact speed
- 44.3 mph
Quick answer
Fall time = sqrt(2h/g); impact speed = g x t.
t = sqrt(2h/g)
How to use the Free Fall Time Calculator
- 1Enter the drop height in metres.
- 2Add an initial downward velocity if the object was already moving.
- 3Read the fall time and impact speed.
Worked example
Using the values the calculator loads with:
Inputs
- Drop height20 m
- Initial velocity0 m/s, down positive
Results
- Fall time2.02 s
- Impact speed19.81 m/s
- Impact speed71.3 km/h
- Impact speed44.3 mph
Frequently asked questions
Does mass affect fall time?
No — in a vacuum all objects fall at the same rate regardless of mass.
What about air resistance?
Light or wide objects like paper fall slower than this ideal model predicts.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.