In response to the growing demand for higher-performance materials while minimizing costs and waste, the importance of miniature testing techniques for characterizing mechanical properties has become undeniable. In this work, the capabilities of the miniature testing techniques, shear punch testing with shear loading mode and small punch testing with biaxial loading state, in characterizing the work-hardening behavior and mechanical properties of austenitic stainless steels were critically discussed and compared with the uniaxial tensile testing method. Moreover, the benefits and drawbacks of these miniature testing methods were elucidated. For this purpose, the metastable AISI 304L stainless steel with a remarkable transformation-induced plasticity (TRIP) effect and the highly stable AISI 904L superaustenitic stainless steel with high solid-solution strengthening were considered. The results showed that these methods can adequately represent the work-hardening behaviors, which can shed light on further utilization of these techniques. Moreover, it was revealed that the high solid-solution strengthening effect in the AISI 904L superaustenitic stainless steel results in a higher yield stress of 349 MPa compared to 217 MPa for the AISI 304L stainless steel. On the other hand, the strong TRIP effect in the AISI 304L stainless steel leads to an ultimate tensile strength of 899 MPa, an ultimate shear strength of 652 MPa, and a maximum load of 3075 N in the small punch test, which are superior compared to the respective values of 793, 513 MPa, and 2356 N for the AISI 904L superaustenitic stainless steel. This research highlighted the potential of miniature testing techniques in accurately simulating work-hardening behavior under varying loading conditions, providing valuable insights that are not only comparable to tensile testing but also offer a practical solution in scenarios where standard-sized specimens are impractical.