We attempted to improve semi-empirical equations for β−-decay in the atomic number range 1≤Z≤42 and mass number range 3≤A≤118. We suggested a semi-empirical formula in terms of an atomic number of daughter nuclei and decay energy in keV. We divided the nuclei into four categories: even(Z)-even(N), even(Z)-odd(N), odd(Z)-even(N), and odd(Z)-odd(N) to propose improved semi-empirical formulae. The existing equation values are compared to the experimental results. When compared to other semi-empirical equations accessible in the literature, the standard deviation produced from the current formula is lower. The improved semi-empirical formulas are of the first kind, requiring only an atomic number of daughter and decay energy during β−-decay. This study discovers a significance in predicting β−-decay.
