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Vertical Free Fall: Height, Time & Speed

Relate vertical drop, elapsed time and arrival speed under constant gravity, including upward initial velocity.

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Enter the known values in the units shown. Results update as you type.
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With gravity 10 m/s² and zero initial velocity, a 20 m drop takes 2 seconds and ends at 20 m/s downward.

Drop = initial velocity × time + ½gt²; arrival velocity = initial velocity + gt

Enter these known values and leave the other values blank.

Gravity is positive and constant; air resistance and other forces are ignored. Initial velocity is positive downward and negative upward.
The endpoint is at or below the starting point, with nonnegative arrival time and downward arrival velocity. Height means net vertical drop, not total path length after an upward launch.
The time formula chooses the descending arrival. For an upward launch returning to the same height, it chooses the later return rather than the initial instant.
The metric starting gravity is 9.80665 m/s²; the imperial starting value is the rounded 32.17405 ft/s². Edit gravity for your conditions. Zero time can be evaluated forward but cannot uniquely determine initial velocity or gravity.

Use a negative initial velocity. The calculator follows its motion until it descends to the stated endpoint at or below its starting height.

No. Terminal velocity requires a drag model. Constant-gravity free fall without air resistance continues to accelerate.

Feet per second squared use exactly 0.3048 meters per second squared, replacing a rounded reciprocal factor.