FreeSWITCH is a free and open-source telephony software for real-time communication protocols using audio, video, text and other forms of media.

The software has applications in WebRTC, voice over Internet Protocol (VoIP), video transcoding, Multipoint Control Unit (MCU) functionality and supports Session Initiation Protocol (SIP) features.

[12] In 2018, SignalWire Inc. was founded to provide commercial cloud telecommunication services utilizing an elastic FreeSWITCH core, and provide a permanent commercial sponsor for the open source project that was controlled by the founders of FreeSWITCH.

According to the original designer, Anthony Minessale, FreeSWITCH is intended to be a softswitch that is built around a core library, driven by a state machine, which can be embedded into other projects.

[11] FreeSWITCH is used to build private branch exchange (PBX), IVR services, videoconferencing with chat and screen sharing, wholesale least-cost routing, Session Border Controller (SBC) and embedded communication appliances.