Dimensional metrology is crucial for the accurate manufacture of parts. X-ray computed tomography (CT) promises to enhance measurements through its unique capability to image inner geometries non-destructively for dimensional analysis. Since establishing traceability is challenging, METAS launched a project with the objective of developing a high-resolution CT system and establishing the associated metrology. In this paper, scaling laws between the resolution and the CT measurement time are analysed. Due to the three-dimensional nature of the data, increasing the resolution scales up measurement times with higher powers, inflicting stringent requirements on the long-term stability of high-resolution CT systems. Solutions, using current and new technologies, are discussed.