AbstractEstimating the magnitude of profile scale factor is currently based on the assumption that beach profiles are in equilibrium condition. However, this assumption cannot be applied to all beach profiles. In this article, a boundary based profile scale factor is proposed that through a normalized coordinate system leads to a unique global profile scale factor. The global profile scale factor helps to determine an initial linear beach profile. The amount of erosion and accretion that causes the initial linear profile to transform to the natural equilibrium beach profile (EBP) can be calculated. Accordingly, the balance between the amount of erosion and accretion will identify a turning point distinguishing the erosion and accretion areas on the profile. This turning point helps to evaluate whether the profile is in equilibrium condition or not. The proposed model was validated through various beach profiles resulting in high degrees of accuracy and reliability.