F5, Inc. is an American technology company specializing in application security, multi-cloud management, online fraud prevention, application delivery networking (ADN), application availability and performance, and network security, access, and authorization.

F5 originally offered application delivery controller (ADC) technology, but has since expanded into application layer, automation, multi-cloud, and security services. As ransomware, data leaks, DDoS, and other attacks on businesses of all sizes are arising, companies such as F5 have continued to reinvent themselves.