Sandy bay beach in static equilibrium is the only physiographic feature that could remain stable without sediment supply in a persistent swell environment anywhere around the world. With a continuing trend of erosion to sandy beaches worldwide, a conservative and practical hypothesis is not to consider the mobile dynamic wave parameters but to safeguard against a sandy beach under vanishing supply in the future. To achieve this, an empirical bay shape equation is strongly recommended as one of the best coastal management options. Combining with MEPBAY, software derived for implementing the static bay beach concept on a display unit, this empirical bay shape equation is readily applicable to verify the stability of numerous headland bay beaches in natural and man-made condition. It is also adequate for coastal managers to apply this empirical equation as a valuable tool to aid in the creation of headland bay beaches for shore protection, recreation, and coastal management before embarking on sophisticated numerical modeling.