The High Definition Geomagnetic Model 2017 (HDGM2017) is a global, high-resolution model (degree 720) of the Earth's geomagnetic main and crustal fields, providing magnetic field values (total field, dip, and declination) at any point above or below the Earth's surface for the year 2017. An optional extension to the HDGM is the HDGM-RT, which provides near real-time estimates of the external disturbance field caused by the solar wind and includes a magnetic field model for daily variations due to ionospheric current systems.