The purpose of this study is to propose a predictor of the vibration level (VL). First, we measured hundreds of accelerograms of ground vibration caused by open pit blastings. VLs were obtained from these accelerograms by the vibration level meter. To estimate the VL, three variables that were considered to be closely connected with VL were chosen, namely, average charge/detonator, W (kg), average time delay. T (ms), distance from the source. D (m), and we assumed the predictor for the VL as follows