A portable shippable automated calibration system for high torque power tools is disclosed. The system includes a self-contained highly durable and shippable container that may comprise a power source, central processor, visual user interface, mechanical interface for coupling with power tools to be calibrated, communications systems for communicating with a power tool being calibrated and/or with on-site or cloud based data systems. The system may be delivered to sites desiring on-site power tool calibration, tools are calibrated and updated calibration factors are automatically uploaded into the calibrated tool and a calibration certificate is published with the particulars of the calibration completion.