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
Matrix reference homeserver
Browse on Tor/i2p, Anon p2p Chat / FileTx, Conf / Video VoIP
Modern, AI-Smart, WASTE p2p for ipv4, Tor and i2p + Voice Conference.
A suite of open-source tools and frameworks for creating SIP apps
Java VoIP Softphone (SIP) (replaced by jfPhone)
http://www.vaakpbx.com
OpenSource Call Center and Dialer System
Free, native Windows SIP softphone with HD audio, SRTP encryption
Cisco IP Phone Inventory - Serial Number, MAC, Model, and more...
For more VoIP resources for business, take a look at the business VoIP category.