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CO-Benefits Risk Assessment Health Impacts Screening and Mapping Tool (COBRA)

  • New! COBRA Desktop and Web Edition 5.0.

    COBRA Desktop Edition and Web Edition can now evaluate the health impacts of ozone (O3) formation, in addition to particulate matter (PM2.5), due to changes in the air pollutants assessed by the model.

  • Develop Your Inputs for COBRA

    Use these factsheets to estimate emissions inputs for COBRA analyses.

  • COBRA in Action

    COBRA has been featured in more than 150 studies and analyses by government agencies, industry experts, academic researchers, and other organizations. See examples of how others have used COBRA. 

Use COBRA

  • Use COBRA Web Edition
  • Download Desktop Edition COBRA
  • User Manual
  • How to Run Scenarios
  • Data for Future Year Scenarios

Watch a Video

Link to  COBRA video

Use Web Edition

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Basic Information

  • What is COBRA?
  • Why use COBRA?
  • Who should use COBRA?
  • How does COBRA work?
  • COBRA Factsheet Series

Learn More

  • Contact EPA about COBRA
  • Frequently Asked Questions
  • Publications that Cite COBRA
  • Get updates about COBRA
  • COBRA Revision History

Download Desktop Edition

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Contact Us to ask a question, provide feedback, or report a problem.
Last updated on April 14, 2025
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