In this paper, a comprehensive online error compensation approach using offline calibration results is proposed for industrial manipulators (with closed control architecture), in order to improve its accuracy. The contents in this paper include a calibration algorithm based on the product-of-exponential formula, an online error compensation procedure for implementing the calibration results on industrial manipulators, and an experimental study that is conducted on a 6-DOF industrial manipulator from ABB (Model: IRB-4400) with a laser tracker system from Leica (Model: AT901-MR) and its Tracker-Machine control sensor. After implementing the proposed online error compensation approach, the accuracy of the ABB industrial manipulator improved to 0.3 mm, thus verifying the effectiveness of the proposed error compensation approach.