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Download COBRA

Notes:

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 5.2 Installer (exe) - Revised March 2025

To install COBRA:

Click on the “COBRA Installer” link above to download the installer. When prompted, choose “Save” and save the file to your computer.
Locate the file “cobra5dot2.exe” on your computer and double-click to run the installer.
Follow all on-screen instructions to complete the installation.
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 March 2025.

Recent Updates

COBRA 5.2 includes the following updates:

Fix for Mortality High and Low Values in Batch Output: A bug in the batch output file caused mortality high and low values to be swapped. This has now been corrected to ensure accurate reporting.
Updated packages: COBRA has been updated with the latest 2025 version of its user interface library (Telerik UI for Winforms). This upgrade ensures continued support, stability, and security against potential vulnerabilities.

This update did not impact the Web Edition of COBRA.

For a summary of all updates to COBRA, please see the COBRA Revision History.

For More Information

For more information, contact cobra@epa.gov.