World Magnetic Model (WMM) coefficient 2020-2025


Jan 23, 2020: PATCH UPDATED. This Mapping and Charting Solutions for Desktop patch updates the World Magnetic Model (WMM) to include the 2020-2025 coefficients. Please download and install this patch at your earliest convenience.


This NEW PATCH updates several coefficients in the 2020- 2025 model. This patch will install on all 10.1 - 10.8.0 Mapping and Charting Solutions for Desktop. We recommend customers with the following solutions download and install this patch to ensure magnetic calculations are current.

  • ArcGIS for Aviation
  • ArcGIS for Maritime: Charting
  • Esri Defense Mapping
  • Esri Production Mapping

Issues Addressed with this patch
GIT1261: Update the World Magnetic Model (WMM) with the 2020-2025 coefficients for use by Esri Mapping and Charting Solutions.

Installing this patch
  1. Make sure you have write access to the installation location.
  2. Select and download the file.
  3. Mapping and Charting Solutions for Desktop 10.1-10.8
    MCS WMM 2020-2025 update Patch
  4. Unzip the file.
  5. Right click the .exe and choose Run as administrator to start the install process.

How to identify which patch is installed

To find out if this patch was installed on a machine, you will need to look at the WMM.xml file date and ensure it is current. The WMM.xml file is installed to the bin directory. Since this patch installs on many different Mapping and Charting versions, use Search to find the WMM.xml.


Check Online Support Center periodically for the availability of additional patches. New information about this patch will be posted here.

Getting Help

If you are in the United States, please contact Esri Technical Support at 1-888-377-4575, if you have any difficulty installing this Patch. Sites outside of the United States, please contact your local Esri software distributor.