Dynamic Pressure Calculator Formula

Understand the math behind the dynamic pressure calculator. Each variable explained with a worked example.

Formulas Used

Dynamic Pressure (q)

q = 0.5 * density * pow(velocity, 2)

Dynamic Pressure

q_kpa = 0.5 * density * pow(velocity, 2) / 1000

Variables

VariableDescriptionDefault
densityFluid Density (rho)(kg/m³)1.225
velocityVelocity (V)(m/s)100

How It Works

Dynamic Pressure

Dynamic pressure represents the kinetic energy per unit volume of a flowing fluid. It is the key scaling parameter for aerodynamic forces.

Formula

q = 0.5 × rho × V²

where rho is the fluid density and V is the freestream velocity. All aerodynamic forces (lift, drag) are proportional to dynamic pressure, which is why it appears in every force coefficient definition.

Worked Example

Air at sea-level standard density flowing at 100 m/s.

density = 1.225velocity = 100
  1. 01q = 0.5 × 1.225 × 100²
  2. 02q = 0.5 × 1.225 × 10000
  3. 03q = 6125 Pa = 6.125 kPa

Ready to run the numbers?

Open Dynamic Pressure Calculator