InversionKit is an interactive Java program which performs linear inversions (rotational or structural) from frequency data. It was written by Daniel Reese and Sergei Zharkov for the European Helio- and Asteroseismology Network (HELAS), a major international collaboration funded by the European Commission's Sixth Framework Programme. Daniel Reese has since then continued development of this code during various postdocs and is currently supported by the SPACEINN network, a major international collaboration funded by the European Commission's Seventh Framework Programme. Some contributions by Gaël Buldgen have also been incorporated in this version of the code.


If InversionKit is used in any publication, the HELAS and SPACEINN networks kindly asks you to acknowledge the use of this software using a phrase such as the following:

"This article made use of InversionKit, an inversion software developed in the context of the HELAS and SPACEINN networks, funded by the European Commission's Sixth and Seventh Framework Programmes."


Version 2.2 Source Compiled version
Version 2.1 Source Compiled version
Version 1.4 Source Compiled version
Version 1.3 Source Compiled version
Version 1.2 Source Compiled version
Version 1.1 Source Compiled version
Version 1.0 Source Compiled version

IMPORTANT: Versions 1.0-1.2 contain an error in the rotational kernels, and versions 1.0-1.3 contain errors in the structural kernels. This has been corrected from version 1.4 onwards.


If you have any enquiries or discover any bugs please write to

Online demo

If given permission, the online version can now run without security restrictions, thanks to the applet signing procedure described on Michael Abramoff's website. Otherwise, it will run in a restricted mode, which prevents opening or saving files.

Copyright information

InversionKit is distributed under the terms of the GNU General Public License, version 3. For more details, see documentation included in the distribution.

GNU GPL, v3, logo

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