The World Magnetic Model and Associated Software

This site provides access to the DoD software and current WMM model and WMM online calculator. The software computes the main components of the geomagnetic field and their annual changes. The programs are designed to be used in demand mode. The software is available as both C and Fortran source code. The model file, WMM.COF, is expected to reside in the same directory as the software. Note: The altitude is referenced to the World Geodetic System 1984 (WGS 84) ellipsoid. The new WMM software library provides functions to convert height above mean sea level (AMSL) to height above WGS 84. This option is enabled by default.

Input And Output

The input parameters and valid entries are:

Latitude -90.00 to +90.00 degrees
Longitude -180.00 to +180.00 degrees
Altitude referenced to the WGS 84 ellipsoid OR the Mean Sea Level (MSL) (downloadable software)
Date 2010.0 to 2015.0

The seven magnetic components computed are:

F - Total Intensity of the geomagnetic field
H - Horizontal Intensity of the geomagnetic field
X - North Component of the geomagnetic field
Y - East Component of the geomagnetic field
Z - Vertical Component of the geomagnetic field
I (DIP) - Geomagnetic Inclination
D (DEC) - Geomagnetic Declination (Magnetic Variation)

Annual change in each of these magnetic components is also displayed. The annual change is computed by subtracting the main field values for the desired input date from main field values one year later. The output units are displayed using the abbreviations nT (nanoTesla), deg (degrees) and min (minutes) per year.

Third party software for World Magnetic Model

Third party software is available here. Note: Neither the authors nor NGDC can provide any warranty or technical support for these programs.

Changes made to the WMM Code

As changes are made to the WMM code, the revised code will be posted. Check this site for change notices .The download code will always be the latest version

Download the World Magnetic Model - WMM2010 - software and documentation.

2KB

Dec 15, 2009

WMM2010 Coefficient file (WMM.COF) valid for 2010 - 2015.

12.4MB

Apr 26, 2012

World Magnetic Model (WMM2010) with the new C software and executables for Windows environment.

3.3MB

Apr 26, 2012

World Magnetic Model (WMM2010) with new C software and executables for Linux environment.

8.2MB

Feb 22, 2010

World Magnetic Model (WMM2010) with Stand-alone Graphical User Interface (GUI) for Windows and C source code.

22MB

Jan 22, 2010

World Magnetic Model (WMM2010) - Technical Report. Note: Older versions of the WMM reports are available here

35KB

Dec 15, 2009

World Magnetic Model (WMM2010) - Test values.

1MB

Dec 15, 2009

World Magnetic Model (WMM2010) with Fortran source code and executables for Windows and Linux environments.

180KB

Feb 4, 2010

World Magnetic Model (WMM2010) with C source code and executables for Windows and Linux environments.