Browse free open source VoIP software and projects below. Use the toggles on the left to filter open source VoIP software by OS, license, language, programming language, and project status.
Issabel PBX - Unified Communications
VoIP SIP and SKINNY quality analyzer and packet / audio recording tool
A simple noise gate app intended for use with VOIPs like Skype.
Unified Communications Server
Java wrapper for the popular chat & VOIP service
Browse over Tor/i2p, Anon p2p Chat/FileTx, p2p ConfVideoVoIP
http://www.vaakpbx.com
Java VoIP Softphone (SIP) (replaced by jfPhone)
High performance, production quality STUN server and client library
An administration web interface for Mumble VoIP servers in PHP
SIP Video Multiconference Media Server with WebRTC support.
Callflow Sequence Diagram Generator
H.323 Gatekeeper for VoIP and videconferencing