Orthanc is free and open-source software. Its source code is freely available to the benefit of hospitals, healthcare professionals, researchers and patients.


Support Orthanc! Developing and maintaining the Orthanc ecosystem requires much work. We would be extremely grateful if you could consider buying support packs or custom developments from our commercial partner Osimis to help us sustain our effort in the long term.

Mailing List

To be informed after each new release of Orthanc, please follow the Orthanc Users discussion group.


Orthanc originates from Sébastien Jodogne's research work at the University Hospital of Liège (Belgium), in the Department of Medical Physics. Orthanc is now primarily developed and maintained by Osimis S.A., spin-off company of the University Hospital of Liège.

The source code of the Orthanc server is jointly copyrighted by the University Hospital of Liège and Osimis S.A. under the GPLv3 license, with the OpenSSL exception. Please pay attention to the fact that Orthanc plugins and viewers may be released under the more restrictive AGPLv3 license.

If the GPL or the AGPL license is too restrictive for your usage, you can buy a license exception by contacting Osimis.

Full information about the licensing of the Orthanc ecosystem is available in the Orthanc Book.

Citing Orthanc

We kindly ask scientific works and clinical studies that make use of Orthanc to cite Orthanc in their associated publications. Similarly, we ask open-source and closed-source products that make use of Orthanc to warn us about this use. You can cite our work using the following BibTeX entry:

  author="Jodogne, S{\'e}bastien",
  title="The {O}rthanc Ecosystem for Medical Imaging",
  journal="Journal of Digital Imaging",

This paper is available for download in open-access courtesy of the Journal of Digital Imaging.