Terminal Velocity Calculator
Calculate the terminal velocity of a falling object from its mass, drag coefficient, air density and area.
How it works
V_t = √(2·m·g / (ρ·C_d·A))
As an object falls it speeds up until air resistance grows enough to cancel gravity; from then on it falls at a constant terminal velocity. Heavier or more compact objects reach higher terminal speeds, while a larger area, higher drag coefficient or denser air slows the fall. A belly-down skydiver spreads out to keep this speed manageable.
Worked example
A 75 kg object with C_d = 1.0, area 0.7 m² in air of density 1.225 kg/m³ (g = 9.81): V_t = √(2 × 75 × 9.81 ÷ (1.225 × 1.0 × 0.7)) ≈ 41.4 m/s (about 149 km/h).
Sources: Terminal velocity — Wikipedia
Frequently asked questions
What is a typical skydiver terminal velocity?
Belly-to-earth, a skydiver reaches roughly 53–56 m/s (about 190–200 km/h). Diving head-first cuts the area and drag coefficient, pushing the speed well past that.
Why does area lower terminal velocity?
Drag rises with cross-sectional area, so a larger frontal area produces more resistance at a given speed, and balance with gravity is reached sooner — at a lower terminal velocity. That is exactly how a parachute works.
What drag coefficient should I use?
It depends on shape: about 0.5 for a sphere, near 1.0–1.3 for a flat plate or a spread human body, and as low as 0.04 for a streamlined shape. Use a value from a reference for your geometry.
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