Kiax started in early 2004 as a small program mainly aimed to provide a simple user interface for making VoIP calls with Asterisk PBX (an open source VoIP PBX). Its first versions showed the existing need for a user-friendly, free and open softphone. Currently Kiax has been downloaded by more than 60 000 users (stats from and is available for direct installation from the repositories of the major Linux distros (Ubuntu, SuSE). While it is functionally rich and considerably stable its development has reached a state where modification and customization became difficult, thus Kiax ver. 2 - the new generation Kiax - faces those requirements with a different architecture.

Kiax ver. 2

Kiax ver.2 is a complete re-write of the softphone which aims to clean up the issues met in the old generation and to provide a more flexible code base for extension and customization. Main supporters of the project are the companies Forschung-Direkt and MIXvoip.

Target goals and features:

  • LGPL-licensed core, GPL GUI
  • Decoupled Signaling, Storage and Visualization aspects
  • Modularized, lightweight core layer
  • GCC4 ready code
  • Single codebase for Linux, Windows and MacOS
  • SQLite as default storage backend
  • QT4.4 as GUI frontend
  • Webkit integration
  • Even simpler (than old Kiax) to use UI
  • Completely brandable
  • Remote configuration
  • Simplified integration with service providers (via JSON)
  • Support for multiple service providers
  • Support for simultaneous calls
  • Registry fail-over support
  • Live CDR and Contacts search
  • Codecs: G711, iLBC, GSM, Speex
  • Noise reduction filter
  • I18n support
  • .TEL resolving of contact data

Kiax ver 2 has been released on 24.09.2008. Binary builds are available for Windows, Linux and Mac OS on SourceForge.
Kiax ver 2.1 Beta 1 has been released on 03.01.2009 and features .TEL functionality - users can save .tel domain names or dial directly .tel domain names where the softphone resolves the contact data.

Home Page:

Kiax 0.8.x (legacy, unsupported)

Kiax is an IAX softphone that uses iaxclient for IAX communication and QT3.x (for Linux) and QT4 (Windows) as GUI.

Despite of the "K" at the beginning of its name, Kiax runs well NOT ONLY ON KDE, but also on other desktop environments. There is a port of its latest version (0.8.51) to Windows based on the GPL version of QT4


  • Multiple registration accounts
  • Multiple call appearances
  • Hold/resume call
  • Call Transfer
  • Noise reduction
  • Echo cancellation
  • AGC
  • Supports ULAW, GSM, iLBC, Speex
  • Grouped Contact List
  • DTMF Dialpad
  • Call Register
  • User-friendly Settings Dialog
  • Customizable User Interface
  • Desktop integration
  • Direct IAX URL dialing possible
  • Command-line dialing possible
  • Command execution on incoming call
  • International Support - English, Czech, German, French, Polish, Bulgarian, Brasilian Portuguese, Macedonian, Malay, Italian, Spanish, Hebrew

Current version: 2.1 Beta1

Legacy version: 0.8.51
NOTE: Please update your Kiax to version 0.8.51 - it fixes security flaw in iaxclient's code, as well as fixes amd64 md5 authorization problem.

Home Page:
Project Page:
Supported Platforms: Linux, NetBSD, FreeBSD (version 0.8.4 in ports), Microsoft Windows (32-bit 2000/XP)
Sources, binaries and installation packages (deb, rpm, .exe) are available via the download page:

Created by: goliamokuche, Last modification: Tue 06 of Jan, 2009 (14:23 UTC) by abstractone
Please update this page with new information, just login and click on the "Edit" or "Discussion" tab. Get a free login here: Register Thanks! - Find us on Google+