A system and a method is disclosed for consistently and verifiably optimizing computed tomography (CT) radiation dose in the clinical setting. Mathematical models allow for estimation of patient size, image noise, size-specific radiation dose, and image quality targets based on digital image data and radiologists preferences. A prediction model estimates the scanner's tube current modulation and predicts image noise and size-specific radiation dose over a range of patient sizes. An optimization model calculates specific scanner settings needed to attain target image quality at the minimum radiation dose possible. An automated system processes the image and dose data according to the mathematical models and stores and displays the information, enabling verification and ongoing monitoring of consistent dose optimization.