Browse free open source VoIP software and projects for Windows 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
A simple noise gate app intended for use with VOIPs like Skype.
Unified Communications Server
Browse on Tor/i2p, Anon p2p Chat / FileTx, Conf / Video VoIP
Java wrapper for the popular chat & VOIP service
Convert VoIP calls to text and analyze them with AI
High performance, production quality STUN server and client library
H.323 Gatekeeper for VoIP and videconferencing
Respins of various open source PBX projects
Positional Audio Communication for Minecraft with Mumble
Java VoIP Softphone (SIP) (replaced by jfPhone)
Modern, AI-Smart, WASTE p2p for ipv4, Tor and i2p + Voice Conference.
Baresip is a modular SIP User-Agent with audio and video support
VoIP/SIP Autodialer