Lift Equation Calculator

About this calculator

The lift equation, L = ½·ρ·v²·A·Cl, is the core relation of fixed-wing aerodynamics: lift force L depends on air density ρ, the square of airspeed v, wing planform area A, and the lift coefficient Cl, which bundles together the airfoil shape and angle of attack. Because lift scales with the square of velocity, doubling airspeed quadruples the available lift, which is why aircraft need far less angle of attack — and much shorter runways — at high speed than at low speed.

Aircraft designers and pilots use this relation to size wings for a target stall speed, to compute takeoff and landing performance, and to understand why lift falls off sharply in thin, low-density air at high altitude. It has the same structure as the drag equation, D = ½·ρ·v²·A·Cd, with the coefficient swapped for the drag counterpart.