This paper deals with the component level breakdown of performance characteristics of a centrifugal compressor using detailed measurements. The compressor stage used for Heavy-Duty applications consisting of the impeller, vaneless diffuser, and volute has been experimentally tested in a gas stand. Several static pressure measurements combined with total pressure and temperature measurements on the compressor stage have been carried out. Based on the detailed measurements, the component level aerothermal performance parameters are calculated on the entire compressor map that includes tip speeds from subsonic to supersonic speeds. The effect of individual component performance characteristics and their impact on the design of the entire stage is discussed both at design and off-design conditions. A better understanding of the component level performance aids to design of a compressor stage for increased efficiency, range, and better surge margin. However, this component-level detailed breakdown of the compressor stage for HD truck application is unavailable in open literature. In addition to the detailed measurements, a 1D model of the impeller is created to correlate measurements with predictions iteratively to identify the relevant 1D modeling parameters for varied tip speeds on the compressor map.