What is dynamic pressure?

Dynamic pressure (symbol q) is the kinetic energy per unit volume of a moving fluid, defined as q = ½ρv², where ρ is fluid density (kg/m³) and v is flow velocity (m/s). It represents the pressure that would result if the fluid were brought to rest, and is a key term in Bernoulli's equation and aerodynamic drag calculations.

What units does dynamic pressure use?

Dynamic pressure is a pressure quantity, so it shares units with pressure: Pascals (Pa), kilopascals (kPa), pounds per square inch (PSI), or pounds per square foot (lb/ft²). This calculator supports all four output units.

What is the density of air at sea level?

Standard air density at sea level (15 °C, 101.325 kPa) is approximately 1.225 kg/m³. Air density decreases with altitude and increases with cold temperatures. For high-altitude or non-standard conditions, enter a custom density.

How is dynamic pressure used in aerodynamics?

Aerodynamic forces such as lift and drag are proportional to dynamic pressure: Lift = CL × q × S and Drag = CD × q × S, where CL and CD are dimensionless coefficients and S is reference area. Dynamic pressure also defines the stagnation pressure at the leading edge of airfoils.

Can I solve for velocity or density instead of pressure?

Yes. Select the target variable from the "Solve for" dropdown. To find velocity, enter q and ρ; the calculator returns v = √(2q/ρ). To find density, enter q and v; the calculator returns ρ = 2q/v².

Dynamic Pressure Calculator

Enter fluid density and velocity to instantly compute dynamic pressure using q = ½ρv², or solve for any one variable from the other two.

Inputs

Solve for

Fluid preset

Fluid Density (ρ)

kg/m³

Flow Velocity (v)

Output unit

Result

Enter values and click Calculate

Common dynamic pressures at a glance

Scenario	Fluid	Velocity	q (Pa)

Summary

Dynamic pressure (q = ½ρv²) is the pressure equivalent of a fluid's kinetic energy. It appears in every aerodynamic force equation and is central to pitot-static airspeed systems, wind-load engineering, and Bernoulli analysis. This calculator solves for dynamic pressure, fluid density, or flow velocity given the other two quantities, and converts results into the unit most useful for your application.

How it works

Select a preset fluid (air at sea level, water, etc.) or enter a custom density.
Choose which quantity to solve for: dynamic pressure, density, or velocity.
Enter the two known values with their units.
Click Calculate to get the result along with the formula substitution.
Switch output units between Pa, kPa, PSI, and lb/ft² as needed.

Use cases

Calculate wind load on a structure or building facade at a given wind speed.
Determine aerodynamic pressure on an aircraft wing or fuselage.
Estimate pitot tube readings in airspeed measurement systems.
Verify Bernoulli equation terms in fluid mechanics coursework.
Find the required airspeed to achieve a target dynamic pressure in a wind tunnel.
Compute drag force inputs for automotive aerodynamics analysis.
Solve for fluid velocity from a measured pressure differential.

Frequently Asked Questions

Last updated: 2026-06-14 · Reviewed by Nham Vu