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Purpose: This study aimed to assess the effect of slicer-based tolerance compensation on the dimensional accuracy (trueness and precision) of dental models fabricated via masked stereolithography (MSLA) 3D printing. It focused on how different offset values affected the internal and external surfaces. Methods: Simplified, hollow, crown-shaped specimens were designed and categorized into four groups (A~D) based on the internal and external tolerance compensation values (−50 μm or 0 μm). Sixteen specimens per group were printed under identical conditions. After post-processing, the models were digitized with a dental scanner. The 3D deviations between the designed data (STEP) and scanned data (STL) were analyzed using Geomagic Control X. Conformity was quantified by root mean square (RMS) values. Results: Trueness analysis showed significant differences (p<0.001). For the internal surface, Group C (–50 μm internal, 0 μm external) showed the highest trueness (lowest RMS). Conversely, Group D (0 μm internal, 0 μm external) showed the highest trueness for the external surface. Precision analysis showed no significant differences among the groups (p>0.05). Color deviation maps confirmed that applying a –50-μm internal tolerance increased the surface area within the acceptable deviation range (±10 μm). Conclusion: Adjusting tolerance compensation in the slicer stage markedly influences the volumetric accuracy of the MSLA-printed dental models. These findings suggest that optimizing distinct tolerance parameters for internal and external surfaces is crucial for improving the dimensional accuracy and clinical fit of dental prostheses in the digital workflow.