This paper gives formulas for analyzing the curling state. Magnetostatic energy of magnetic thin films having volume and surface charges can be calculated from the formulas, expressed in terms of film thicknessT, film widthW, saturation magnetizationM, length of curling regionD, and angle &thgr;0between the magnetic moment and the film edge surface. Using the formulas, we have quantified the magnetization distribution in the film edge layer and the decrease in energy caused by conversion from surface charges into volume charges.