Additive manufacturing (AM) or 3-D printing refers to a new class of technologies that actively construct products directly from any 3-D digital model. In the future, the broader applications of AM will require a cost reduction of AM machines. Currently, the products fabricated by low-end machines, such as those fabricated using fused deposition modeling (FDM) processes, suffer from the issue of low dimensional accuracy due to multiple error sources. To properly manage error sources for improved prevision, this paper proposes a novel strategy for error compensation in the FDM processes. First, we consecutively attribute the dimensional inaccuracy to two major error sources that affect the geometric shape of the product: 1) positioning error of the extruder and 2) shape deformation induced by processing error, including material phase change and other variations that occur. The extruder positioning error is characterized by a Kriging model, while the modeling of shape deformation due to processing error follows the method developed by Huang et al. Second, using error equivalence concept, we transform the positioning error into the equivalent amount of design input error. Finally, we adjust the design to compensate for the overall shape deviation. To validate this strategy, we conduct a designed experiment for the shape deviation prediction and the compensation. The experimental results successfully demonstrate the effectiveness of the proposed three-step strategy to manage multiple error sources in the FDM processes. Note to Practitioners-At present, the shape deviation of the product hinders the application of additive manufacturing in extensive industries. This paper propose an in-plane compensation plan for a fused deposition modeling (FDM) process. Mathematical models are built to predict the deviation of a 2-D shape, and a compensation algorithm is derived based on this model. With the methodology described in this paper, a special compensation system can be developed for an FDM machine. This system analyzes the measurement of specifically designed test products, derives a compensation plan, and modifies any 2-D computer-aided design model to increase the shape fidelity of the product.