Free Fall Time Calculator
Enter height, initial vertical velocity, and gravitational acceleration using the stated units; air resistance is excluded.
A QUICK WALKTHROUGH
How to use this tool
- Enter height in metres, initial velocity in m/s, and g in m/s².
- Calculate the positive time root.
- Review the ideal final velocity and its sign.
Ideal equation
For upward-positive vertical motion from the stated height, the ground time is t = (v₀ + √(v₀² + 2gh)) / g. Final velocity is v₀ − gt.
Units and signs
Height is metres, initial and final velocity are metres per second, and g is metres per second squared. Positive initial velocity is upward; negative final velocity means downward in this convention.
Model limits
This is an ideal mathematical model with constant g and no air resistance, wind, rotation, terrain, or object characteristics. It is not a real-motion or safety prediction.
GOOD TO KNOW
Common questions
Can initial velocity be negative?
Yes. Negative means downward in the stated sign convention; the calculator still returns the positive time root when the inputs are valid.
Does it include air resistance?
No.
Is this a safety prediction?
No. Real motion depends on conditions not represented by this model.