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Energy Resources for State and Local Governments

Download COBRA


  • The installer file is large, and may take some time to download, depending on connection speed.
  • A Windows computer is necessary to use the tool.
  • COBRA Installer (EXE)(502 MB)  - Revised June 2020

To install COBRA:

  1. Click on the “COBRA Installer” link above to download the installer. When prompted, choose “Save” and save the file to your computer.
  2. Locate the file “cobradontnetv4dot0.exe” on your computer and  double-click to run the installer.
  3. Follow all on-screen instructions to complete the installation.
  4. To run COBRA, look for the “COBRA” entry in your “Start” menu.

If you have a previous installation of COBRA on your computer, uninstall it before installing the latest version of COBRA.

For detailed installation and usage instructions, reference the revised COBRA User Manual (PDF) – revised June 2020.

Recent Updates

Versions of COBRA prior to 2.614 contained unmodified source code under the MPL 1.1. This source code is available upon request or at Exit

For More Information

For more information, contact Emma Zinsmeister, ( at 202-343-9043.