<p>The pseudo-Compact Tension (pCT) test is an established method for determining Mode I fracture toughness in brittle geomaterials. However, its conventional implementation relies on specialized equipment with complex design and manufacturing, which can limit its accessibility and practical application. This study introduces a simple loading fixture, referred to as the shear-to-tensile (ST) tool, which enables pCT testing using a standard direct shear apparatus. The proposed setup allows testing under both dry and submerged conditions and allows full capture of the post-peak response. Eighteen gypsum specimens with varying notch lengths were tested, and the results were compared with those obtained from semi-circular bend (SCB) and cracked straight-through Brazilian disc (CSTBD) methods. The mechanical performance of the system was further evaluated through three-dimensional finite element simulations, confirming its adequate stiffness and structural integrity. The pCT tests produced fracture toughness values comparable to those from the SCB and CSTBD methods, with lower variability, indicating improved consistency. Submerged tests on specimens with 21% saturation showed a 29% reduction in fracture toughness, demonstrating the capability of the setup to capture saturation effects. Overall, the proposed loading fixture provides a reliable and accessible approach for fracture toughness testing using pCT specimens, although its applicability to stronger rocks remains to be validated.</p>