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, project status, and freshness.
VoIP SIP and SKINNY quality analyzer and packet / audio recording tool
Issabel PBX - Unified Communications
Unified Communications Server
A simple noise gate app intended for use with VOIPs like Skype.
Browse over Tor/i2p, Anon p2p Chat/FileTx, p2p ConfVideoVoIP
Java wrapper for the popular chat & VOIP service
Matrix reference homeserver
http://www.vaakpbx.com
OpenSource Call Center and Dialer System
Callflow Sequence Diagram Generator
An administration web interface for Mumble VoIP servers in PHP
Positional Audio Communication for Minecraft with Mumble
Java VoIP Softphone (SIP) (replaced by jfPhone)
For more VoIP resources for business, take a look at the business VoIP category.