A calibration method/system and verification method for digital torque tools are disclosed, in which the calibration method comprises the steps of: transmitting a data containing usage records of a digital torque tool at a client end to a remote calibration platform; comparing the data of usage records with statistic data stored in the calibration platform so as to obtain a data relating to average degree of fatigue; performing a calculation based upon the data of usage record and the data of average degree of fatigue so as to obtain a calibration data; transmitting the calibration data to the client end while allowing the calibration data to overwrite the corresponding original torque data of the digital torque tool.