🪂 Terminal Velocity Calculator
Enter mass, frontal area, drag coefficient and fluid density to get the terminal velocity, in m/s, km/h and mph.
Terminal velocity
42.78 m/s
= 154 km/h · 95.69 mph
Terminal velocity is the steady falling speed where drag balances weight: v = √(2mg ÷ (ρ·A·Cd)), with ρ the fluid density, A the frontal area and Cd the drag coefficient. A belly-down skydiver reaches about 55 m/s (200 km/h); a streamlined dive is much faster. 🔒 In your browser.
How the terminal velocity calculator works
A falling object speeds up until the upward drag force equals its weight; after that it falls at a constant terminal velocity. Setting drag equal to weight and solving gives v = √(2mg ÷ (ρ·A·Cd)), where m is mass, g gravity, ρ the fluid density, A the frontal (cross-sectional) area and Cd the drag coefficient. Presets are included for common drag coefficients and for air and water.
Terminal velocity rises with mass and falls with area and drag, which is why a feather and a hammer fall together only in a vacuum. A belly-down skydiver reaches roughly 55 m/s (about 200 km/h); a head-down dive can exceed 90 m/s. The Cd and area are approximate for real, tumbling bodies, so treat the result as an estimate.
Frequently asked questions
What is terminal velocity?
The constant speed a falling object eventually reaches when air resistance (drag) exactly balances its weight, so the net force, and acceleration, is zero. It keeps falling, but no longer speeds up.
How do you calculate terminal velocity?
v = √(2mg ÷ (ρ·A·Cd)), where m is mass, g = 9.81 m/s², ρ the fluid density, A the frontal area and Cd the drag coefficient. Heavier or more streamlined objects have higher terminal velocities.
What is the terminal velocity of a human?
About 55 m/s (roughly 120 mph or 200 km/h) for a skydiver falling belly-down, and up to ~90 m/s in a streamlined head-down dive. It depends on body position, which changes the area and drag.
Why do heavier objects have a higher terminal velocity?
Because weight (which drives the fall) grows with mass, while drag depends on area and speed. A heavier object needs a higher speed for drag to catch up to its greater weight, so it falls faster before balancing out.
Does terminal velocity depend on the fluid?
Yes, the denser the fluid, the more drag and the lower the terminal velocity. The same object falls far slower in water (ρ ≈ 1000 kg/m³) than in air (ρ ≈ 1.225 kg/m³). Set the fluid density accordingly.