The secretome contains all the Excreted/Secreted (ES) proteins of a cell. These proteins are involved in critical biological processes, such as cell-cell communication, signal transduction and modulating the host immune response. Recently, we introduced the abundance of antigenic regions (AAR) value to assess the antigenic density of a protein and to evaluate the antigenic potential of predicted and experimental secretomes. Now, to facilitate the AAR calculation at genome-scale level by a broader community, we implemented it as a user-friendly web server harvesting local CPU resources. Additionally, we extended the web server capabilities implementing a tool to identify if a protein belongs to the most comprehensive predicted and experimental secretomes for the human pathogens Mycobacterium tuberculosis and Taenia solium. The web server can be a useful tool for those researchers working on immunoinformatics, mainly aiming at discovering candidates for new vaccine or diagnostic tests, and it can also help to prioritize the experimental analysis of potential protein for druggability assays. Secret-AAR is available at: http://microbiomics.ibt.unam.mx/tools/aar/index.php.