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🪂 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.

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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.

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