Although scholars imply that job crafting contributes to person-job fit and meaningful work, to date, no study examined the relationships between these variables. The present three-wave weekbook study was designed to gain more knowledge about the influence of job crafting on person-job fit and meaningfulness. We collected data among a heterogeneous group of employees (N = 114) during three consecutive weeks (N = 430 occasions). At the end of their working week, employees reported their job crafting behaviors, their person-job fit (demands-abilities fit and needs-supplies fit), and the meaningfulness of their work that week. Results indicated that individuals who crafted their job by increasing their job resources (e.g., support, autonomy) and challenging job demands (e.g., participate in new projects), and by decreasing their hindering job demands (e.g., less emotional job demands) reported higher levels of person-job fit the next week. In turn, demands-abilities fit related to more meaningfulness in the final week. No support was found for alternative causal models. These findings suggest that by crafting their job demands and job resources, individuals can proactively optimize their person-job fit and as a consequence experience their work as meaningful.