Abstract Cognitive job demands in the JD‐R theory are surprisingly underexplored. Despite extensive research using the JD‐R model, we lack a comprehensive understanding of how cognitive job demands affect employee well‐being and do not have a widely accepted definition of these demands. This is particularly concerning, as cognitive job demands have become a crucial characteristic of the 21st‐century work environment, especially with increasing job complexity and technological advancements such as AI. Therefore, in this conceptual paper, we draw on cognitive and work psychology research to explore the concept of cognitive job demands within the JD‐R and propose a typology of these demands. We address three key questions: (1) How can cognitive job demands be defined? (2) Are cognitive job demands a challenge demand, a hindrance demand or potentially even a job resource? (3) What roles do personal and job resources play in managing cognitive job demands? This paper aims to explore cognitive demands and their effects on employees, laying the foundation for future research on the changing cognitive nature of contemporary jobs within the JD‐R framework. Our questions about cognitive demands also raise important challenges for broader JD‐R research, leading to proposals for the further development of the JD‐R theory.