The Lift Equation Calculator features the lift equation solved for each of its component.  The force of lift equation is:

`F_L = 1/2*A*rho*C_L*V^2`

where:

• (F_L) - Force of Lift
• (C_L) - Lift Coefficient 
• (A) - Wing Surface Area
• (V) - Velocity of Air over the Wing
• (ρ) - Density of air (default is the dry air density)

Density of Air

The density of air, ρ (Greek: rho) (air density), is the mass per unit volume of Earth's atmosphere. Air density, like air pressure, decreases with increasing altitude. It also changes with variation in temperature or humidity. At sea level and at 15 °C, air has a density of approximately 1.225 kg/m³ (0.001225 g/cm³, 0.0023769 slug/ft³, 0.0765 lbm/ft³) according to ISA (International Standard Atmosphere).

• At IUPAC standard temperature and pressure (0 °C and 100 kPa), dry air has a density of 1.2754 kg/m³ (the default above).
• At 20 °C and 101.325 kPa, dry air has a density of 1.2041 kg/m³.
• At 70 °F and 14.696 psi, dry air has a density of 0.074887lb_m/ft³.

References

• Wikipedia - https://en.wikipedia.org/wiki/Lift_(force)
• Wikipedia - http://en.wikipedia.org/wiki/Density_of_air