A method for optimizing Specific Absorption Rate (SAR) estimation using a Magnetic Resonance Imaging (MRI) Scanner includes detecting movement of a table holding a patient into a bore of the MRI Scanner and, while the table is moving into the bore, performing an MRI scan of the patient to acquire a multi-slice multi-dimensional MRI dataset of an anatomical region of interest of the patient. The multi-slice multi-dimensional MRI dataset is processed to obtain a three-dimensional model corresponding to the patients body geometry. Then, a patient-optimized SAR estimation is calculated using the three-dimensional model of the patients body geometry.