Geomagnetic Model Web Service: Available Models The World Magnetic Model (WMM) revision 2020 is available through this web service. To use this model, set the 'model' parameter to 'WMM' and the 'revision' parameter to '2020'. Valid dates for this model are from 2020 to 2030, though reduced accuracy should be expected for dates beyond 2025 The International Geomagnetic Reference Field (IGRF) revision 13 is available through this web service. To use this model, set the 'model' parameter to 'IGRF' and the 'revision' parameter to '13'. The BGS Global Geomagnetic Model (BGGM) revisions 1994 to 2023 are available through this web service. To use this model, set the 'model' parameter to 'BGGM' and the 'revision' parameter to a value between '1994' and '2023'. The BGS Global Geomagnetic Model (BGGM) error model revisions 2019 to 2023 are available through this web service. To use this model, set the 'model' parameter to 'BGGMERR' and the 'revision' parameter to a value between '2019' and '2023'. For any model the 'revision' can be set to 'current' to use the most recent revision. To see general information about this web service the 'general' help page (link = general) To see information about parameters view the 'parameters' help page (link = parameters)