Several different integral times at multiple temperatures added by the attenuators are often required for the wide dynamic range infrared radiometric systems. It′s not only inefficient, time-consuming and costly, but also affects real-time and mobility when used for the missions. Based on the calibration model considered integral time, the high-speed calibration algorithm was proposed for wide dynamic range and random integral time. The algorithm can obtain calibration equation for wide dynamic range and random integral time mainly by only turning one temperature point and one integral time point. The verifying experiments were performed by the Φ400 mm infrared radiometric systems, for purpose of the accuracy of calibrations and measurements by the algorithm mentioned above. Experimental results show that the high-speed calibration algorithm compared with the direct calibration results maximum error is 2.75%, the maximum error radiant measurement is 11.69% and the maximum error compared to the conventional radiant measurement result is not more than 1.52%. The high-speed calibration algorithm can improve the efficiency of radiometric calibration, shorten the calibration time and achieve the equation of calibration at random time on the premise of the accuracy of consequences. The entire process of mission is real-time, simple operation, high reliability, easy to implement and suitable for the measurement requirements to infrared radiometric system, that can be directly applied to the target range of infrared radiometric missions.