Wind tunnel corrections are investigated for two-dimensional low-speed wind tunnel tests that are performed for three similar airfoils for angles of attack ranging from −180° to 180° at Re = 0.75 × 106. Aided by the Blasius theorem, wind tunnel corrections are deduced for the lift, drag and pitching moment of the airfoil at high angles of attack. The wall pressure signature method is applied to determine the strengths of the equivalent singularities. The tunnel wall-induced force and pitching moment are obtained by calculating the force and moment exerted on the equivalent singularities. The maximum correction for drag is determined to be about 50%. The corrected forces and pitching moments for three similar airfoils are coincident with one another. A method to determine an optimum singularities distribution range is presented. The results indicate that the correction method in the paper is effective for airfoil testing at high angles of attack. Copyright © 2014 John Wiley & Sons, Ltd.