This paper discusses the performance of the first CrIS flight instrument and its data product performance. Together with ATMS, the CrIS sensor is a critical payload for National Polar-orbiting Operational Environmental Satellite System (NPOESS) and will first fly on the NPOESS Preparatory Project (NPP) mission, the risk reduction flight for NPOESS. NPOESS is the next generation weather and climate monitoring system for the U.S. Air Force and National Oceanic and Atmospheric Administration (NOAA), being developed under contract by Northrop Grumman Aerospace Systems. This paper describes instrument radiometric performance such as calibrated spectral response shape, error residuals and absolute spectral calibration of the CrIS Flight Model 1 (FM1) sensor including the signal processing algorithms used to radiometrically and spectrally calibrate the CrIS sensor. This includes a description of the CrIS ground algorithms that convert Raw Data Records (RDR) into calibrated Sensor Data Records (SDR) and then the SDRs into Environmental Data Records (EDR).