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FreeSWITCH
What it is
FreeSWITCH is an open-source framework for real-time voice and video. It can route calls, bridge video, transcode media, and connect protocols, and the maker describes it as infrastructure for carriers, contact centers, and communication products. The software is available under the MPL license and can run in production at no cost.
Its Event Socket makes call control, channel management, and internal events available to external processes over TCP. Integration options include HTTP backends, embedded Lua, Perl, Python, JavaScript, Java, and SignalWire connectivity. The mod_signalwire module connects FreeSWITCH to SignalWire for inbound and outbound PSTN calling over a persistent WebSocket session. Linux installation documentation covers Debian and Ubuntu using SignalWire packages or a source build. A free SignalWire account is required to access packages and downloads. Self-hosting calls for dedicated resources to maintain on-premises infrastructure. Community support is available for the open-source edition; FreeSWITCH Pro offers commercial support, hardened builds, and priority patches.
For and against
For
- Can route calls, bridge video, and transcode media.
- Production use is permitted at no cost.
- Event Socket exposes call control over TCP.
- Supports integrations in several languages and through HTTP.
- Supports inbound and outbound PSTN calling via SignalWire.
Against
- A free SignalWire account is needed for downloads.
- Self-hosting requires dedicated infrastructure maintenance resources.
- Open-source edition support is community-based.
The verdict
FreeSWITCH offers a no-cost, open-source foundation for voice and video systems, with call controls and multiple integration routes. Teams should account for the download requirement and the resources needed to run self-hosted infrastructure.
Who it suits
FreeSWITCH suits teams building voice or video communication systems that can operate self-hosted infrastructure. Its open-source edition offers community support, while commercial support is available through FreeSWITCH Pro.
Plans and prices
FreeSWITCH Open Source
Self-hosted · MPL 2.0 · Community support
Read 3 Oct 2026 · signalwire.com
FreeSWITCH Advantage
Self-hosted · Commercial modules (G.729A, AMD) · Founder-level support
Read 3 Oct 2026 · signalwire.com
SignalWire Platform
Cloud-hosted · Programmable layer around FreeSWITCH media engines
Read 3 Oct 2026 · signalwire.com
On the record
- Call control
- The Event Socket exposes call control, channel management, and the internal event system over TCP to external processes.developer.signalwire.com · read 3 Oct 2026
- Commercial modules
- The commercial modules include answering machine detection and licensed G.729 Annex A encoding and decoding for transcoding.developer.signalwire.com · read 3 Oct 2026
- Downloads
- A free SignalWire account is required to access FreeSWITCH packages and downloads.signalwire.com · read 3 Oct 2026
- Integrations
- FreeSWITCH documents integrations through HTTP backends, embedded Lua, Perl, Python, JavaScript and Java, and SignalWire connectivity.developer.signalwire.com · read 3 Oct 2026
- License
- FreeSWITCH is open source under the MPL license and can be run in production at no cost.signalwire.com · read 3 Oct 2026
- Linux support
- The getting-started guide documents installation on Debian and Ubuntu using SignalWire packages or a source build.developer.signalwire.com · read 3 Oct 2026
- Maintainer
- SignalWire says it was founded by the original FreeSWITCH creators and is the project's primary maintainer.signalwire.com · read 3 Oct 2026
- Operational requirement
- For self-hosting, the maker says teams should have dedicated resources to maintain on-premises infrastructure.signalwire.com · read 3 Oct 2026
- Purpose
- FreeSWITCH is an open-source framework for real-time voice and video that can route calls, bridge video, transcode media, and connect protocols.signalwire.com · read 3 Oct 2026
- Security controls
- FreeSWITCH supports named IP allow and deny network lists that can be used by SIP profiles and the Event Socket.developer.signalwire.com · read 3 Oct 2026
- SignalWire connectivity
- The mod_signalwire module connects FreeSWITCH to SignalWire for inbound and outbound PSTN calling over a persistent WebSocket session.developer.signalwire.com · read 3 Oct 2026
- Support
- The open-source edition has community support, while SignalWire offers commercial support, hardened builds, and priority patches through FreeSWITCH Pro.signalwire.com · read 3 Oct 2026
- Use cases
- The maker describes FreeSWITCH as powering carriers, contact centers, and communication products.signalwire.com · read 3 Oct 2026
