A firm’s absorptive capacity -its ability to recognize, assimilate, and exploit knowledge- has been viewed as one of the most investigated constructs in organizational research over the last two decades. Knowledge as a focal antecedent of absorptive capacity has been studied extensively. However, the results represent fundamentally different aspects of knowledge which has led to a fragmentation of the literature. Thus, it remains unclear which dimensions of knowledge are relevant for the development of absorptive capacity. By applying meta-analytical methods in 156 samples representing 284,144 firms, we examine the links between different knowledge antecedents and absorptive capacity, considering knowledge forms (knowledge assets and routines and processes), knowledge characteristics (quantity and quality) as well as knowledge contexts (firm internal and inter-firm). While our findings display significant positive impact of different knowledge antecedents on absorptive capacity, these relationships vary in strength. Our findings confirm the relevance of knowledge routines and processes and firm internal quality of knowledge for the development of absorptive capacity. Interestingly, the quantity of knowledge a firm possesses appears to be less important. Our results furthermore suggest knowledge antecedents to be more relevant in the firm internal context. This challenges the general assumption in the absorptive capacity literature, which emphasizes the importance of inter-firm cooperation for the development of absorptive capacity. In our post-hoc test, we extend our conceptual model and assess absorptive capacity’s mediating role between knowledge antecedents and innovation. We provide a fine-grained, integrated framework on absorptive capacity’s knowledge antecedents, highlighting their differential importance for absorptive capacity.