Abstract: Systems and methods for correcting received magnetometer coordinates of a measured magnetic bearing are disclosed. The measured magnetic bearing may be received from a calibrated magnetometer configured to measure the strength and direction of a magnetic field. In embodiments used to navigate a geographical area, the magnetic field comprises, at least in part, Earth's magnetic field. The magnetic field is subject to anomalies caused by metal structures in the vicinity of the magnetometer. The corrected magnetic bearing is based on a slope of the coordinates relative to a defined origin and a magnetic field constant, such as Earth's magnetic field constant. In some embodiments, the received magnetometer coordinates are filtered prior to correction. In some embodiments, a magnitude of the measured magnetic bearing relative to the defined origin is compared to an anomaly detection limit and a bearing validity indicator is output according to the result of the comparison.