NCEI products and services are now available. Many data products continue to be updated as a result of the outage caused by Hurricane Helene. We apologize for any inconvenience.
Geomagnetism is one of the oldest geophysical sciences. Geomagnetic fields have been observed and used since ancient times, and are still used for modern applications in navigation and mineral exploration. NCEI develops and distributes models of the geomagnetic field and maintains archives of geomagnetic data to further the understanding of Earth magnetism and the Sun-Earth environment.
This map displays modeled changes in the location of the magnetic poles calculated for the years 1590-2025.
A mobile app with a digital compass that can calculate the magnetic field in your area.
Geomagnetic Calculators can be used to measure different aspects of the magnetic field for specific time frames and coordinates.
This map displays historical isogonic lines and magnetic poles calculated for the years 1590–2025.