Calculate wind resistance (drag force) from wind speed and the area facing the wind, with typical drag coefficients and air density, or solve for speed.

Use the wind speed relative to the object and the area facing the wind.

Use the same area convention as the selected Cd.

Typical published Cd for the shape. Pick Custom if you know your object’s Cd.

1.225 is standard sea-level air at 15 ยฐC. Use about 1.0 at 2,000 m altitude.

Load multiplier
Blank means1. This multiplies force, not speed; it is not a code wind-load factor.

Related Calculators

Wind Resistance Formula

The following formula is used to calculate the wind resistance on an object:

WR = 0.5 ร— Cd ร— ฯ ร— A ร— Vยฒ

Variables:

  • WR is the wind resistance (N)
  • Cd is the drag coefficient (dimensionless)
  • ฯ is the air density (kg/mยณ)
  • A is the projected reference area matching the drag coefficient (mยฒ)
  • V is the velocity relative to the air (m/s)

Multiply0.5 by drag coefficient, air density, its matching projected reference area and squared air-relative speed. The optional load multiplier scales this force; it does not multiply wind speed or represent a building-code factor. Reverse speed is โˆš(2F/(ฯCdAร—multiplier)). The displayed Fร—air-relative-speed power equivalent represents propulsion power only for motion through still air; a stationary object in wind has zero translational mechanical power.

What is Wind Resistance?

Wind resistance, also known as air resistance or drag, is the force exerted by air on an object moving through it. Drag opposes motion relative to the air and, with density, area and coefficient fixed, increases with squared air-relative speed. It is an important factor in various fields such as automotive design, aerospace engineering, and sports science.

How to Calculate Wind Resistance?

The following steps outline how to calculate the wind resistance on an object:

  1. First, determine the velocity (V) of the object relative to the air in meters per second (m/s).
  2. Next, determine the cross-sectional area (A) of the object facing the wind in square meters (mยฒ).
  3. Next, determine the drag coefficient (Cd) of the object, which is a dimensionless number.
  4. Next, determine the air density (ฯ) in kilograms per cubic meter (kg/mยณ).
  5. Next, gather the formula from above: WR = 0.5 * Cd * ฯ * A * Vยฒ.
  6. Finally, calculate the wind resistance (WR) in newtons (N).
  7. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem:

Use the following variables as an example problem to test your knowledge.

Velocity (V) = 15 m/s

Cross-Sectional Area (A) = 2 mยฒ

Drag Coefficient (Cd) = 1.05

Air Density (ฯ) = 1.225 kg/mยณ. With multiplier1, the result is289.40625N (about65.0611lbf), with dynamic pressure137.8125Pa.