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
http://www.vaakpbx.com
Browse on Tor/i2p, Anon p2p Chat / FileTx, Conf / Video VoIP
High performance, production quality STUN server and client library
H.323 Gatekeeper for VoIP and videconferencing
OpenSource Call Center and Dialer System
Java VoIP Softphone (SIP) (replaced by jfPhone)
survey research software integrate for CATI/ CAWI/ CAMI survey
An administration web interface for Mumble VoIP servers in PHP
Modern, AI-Smart, WASTE p2p for ipv4, Tor and i2p + Voice Conference.
For more VoIP resources for business, take a look at the business VoIP category.