Enter the force of drag, the density of the fluid, velocity, and frontal area of the body. The calculator will display the drag coefficient of this object.

Drag Coefficient Formula

The following formula is used to calculate the drag coefficient of an object.

Cd = Fd / 1/2*p*V^2*A
  • Where Cd is the drag coefficient
  • Fd is the force due to drag
  • p is the density of the fluid
  • v is the velocity
  • A is the frontal area

Drag Coefficient Definition

A drag coefficient is a unitless measure of the resistance to movement through a fluid an object has due to its shape.

How to calculate a drag coefficient?

How to calculate a drag coefficient?

  1. First, determine the drag force acting on the object

    Something that’s fairly unique about the coefficient of drag, is that it needs to be calculated using experimental data. To date, there is no accurate way to calculate it with data. So, in order to calculate the coefficient, a test needs to be set up that allows one to measure the force acting on the object.

  2. Next, measure the velocity and density of the fluid

    Using your test setup information, or device, determine the velocity of the fluid moving around the object. (This could also be the velocity of the object itself.)

  3. Next, measure the frontal area

    Calculate or measure the frontal area of the object. This is the area exposed to the force of drag.

  4. Calculate

    Calculate the drag coefficient using the information from the steps above.


What is a drag coefficient?

A drag coefficient is a coefficient used to describe how aerodynamic a certain object is. That is, how much force acts on an object moving through a fluid relative to its size and the flow speed.

How can you reduce drag?

This is done by reducing the drag coefficient. Decrease the frontal area and change the shape to change the coefficient.

drag coefficient calculator
drag coefficient formula