• Pidgin icon

    Pidgin

    Pidgin is an easy to use, multi-protocol chat client client used by millions. Connect to AIM, MSN, Yahoo, XMPP, and more chat networks all at once. It has built-in support for NSS, offering client-to-server message encryption for...

    Open Source Mac Windows Linux BSD PortableApps.com Xfce

  • Jitsi icon

    Jitsi

    Jitsi (previously SIP Communicator) is an audio/video and chat communicator with full end-to-end encryption that supports protocols such as SIP, XMPP/Jabber, ICQ/AIM, Windows Live, Yahoo!, GTalk/Hangouts extensions, as well as OTR...

    Open Source Mac Windows Linux Web / Cloud Android BSD

  • Adium icon

    Adium

    Adium is a free and open source instant messaging application for Mac OS X, written using Mac OS Xs Cocoa API, released under the GNU GPL and developed by the Adium team. Based on the libpurple protocol library, Adium can connect you...

    Open Source Mac

  • ICQ icon

    ICQ

    ICQ is one of the oldest instant messengers. First developed by the Israeli company Mirabilis, sold to AOL, sold again and currenly owned by the Russian "mail.ru" group (known for one of the largest social networks). ICQ has...

    Free Mac Windows Linux Web / Cloud Android Windows Mobile ... iPhone Java Mobile S60 Blackberry Android Tablet Windows Phone iPad Kindle Fire

  • Franz icon

    Franz

    Franz is a free messaging app / former Emperor of Austria and combines chat & messaging services into one application. Franz currently supports Slack, WhatsApp, WeChat, HipChat and many more. You can download Franz for Mac...

    Free Mac Windows Linux

  • iMessage icon

    iMessage

    Love iMessage on your iPhone? You'll love it on your Mac, too. Messages lets you send unlimited messages to anyone on a Mac, iOS device, or Apple Watch. Your messages can include photos, videos, documents, audio, and contacts, and...

    Free Mac iPhone iPad Apple Watch

  • Quassel IRC icon

    Quassel IRC

    Quassel IRC is a modern, cross-platform, distributed IRC client based on the Qt4 framework. Distributed means that one (or multiple) client(s) can attach to and detach from a central core that stays permanently online -- much like the...

    Open Source Mac Windows Linux Self-Hosted

  • ooVoo icon

    ooVoo

    Free high quality video chat and video conferencing from ooVoo. Talk live face-to-face with up to 6 people at once.

    Freemium Mac Windows Android iPhone Windows Phone Android Tablet ... iPad Kindle Fire

  • Spark icon

    Spark

    Spark is an Open Source, cross-platform IM client optimized for businesses and organizations. It features built-in support for group chat, telephony integration, and strong security. It also offers a great end-user experience with...

    Open Source Mac Windows Linux Self-Hosted

  • Psi+ icon

    Psi+

    Psi+ is a development branch of Psi IM XMPP/Jabber client. Psi is a cross-platform powerful XMPP/Jabber client (Qt, C++) designed for the Jabber power users.

    Open Source Mac Windows Linux BSD

  • Know any more alternatives to Trillian?

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  • Instantbird icon

    Instantbird

    Instantbird is an instant messaging client based on Mozilla XULRunner and the open source library libpurple created by the software developers of Pidgin . Over 250 add-ons allow user customization...

    Open Source Mac Windows Linux PortableApps.com

  • Rambox icon

    Rambox

    Free, Open Source and Cross Platform messaging and emailing app that combines common web applications into one.

    Open Source Mac Windows Linux

    • Warning The installer contains a trojan and possibly other malware according to Baidu, Quihoo-360, and Windows Defender: https://www.virustotal.com/en/file/16f58286c4760fd44896d3dd7a39276a769d301d3193083a130b7a6cd2e03a8d/analysis/1482115813/ | https://www.virustotal.com/en/file/a32e5006f0e227d88a8c8446c0e288bdc4c2a1fb4e9af5ea24a1819131a21ca5/analysis/1482115816/
  • Kopete icon

    Kopete

    Kopete is an instant messenger supporting AIM, ICQ, MSN, Yahoo, Jabber, IRC, Gadu-Gadu, Novell GroupWise Messenger, and more. It is designed to be a flexible and extensible multi-protocol system suitable for personal and enterprise...

    Open Source Mac Linux BSD

  • Zulip icon

    Zulip

    Powerful open source group chat. Features: Threaded group conversations Talk about multiple topics at once without getting lost or overwhelmed. One-on-one and group private conversations Have private conversations with one...

    Open Source Mac Windows Linux Web / Cloud Android iPhone ... BSD Self-Hosted

  • YakYak icon

    YakYak

    What does it do: * Send/receive chat messages * Create/change conversations (rename, add people) * Leave/delete conversation * Notifications * Toggle notifications on/off * Drag-drop, copy-paste or...

    Open Source Mac Windows Linux

  • Bleep icon

    Bleep

    Private instant messaging via secure, distributed technology. Download & Go Enjoy the benefits of having an account without the hassle of creating one. Simply download the app, invite your friends and start chatting. ...

    Free Mac Windows Android iPhone iPad Android Tablet

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  • KakaoTalk icon

    KakaoTalk

    KakaoTalk is a phone number based messenger service that allows users anywhere in the world to chat one-to-one or in a group for free. (no SMS service) Message arrivals are instantly notified with Push Alert and you can send...

    Freemium Mac Windows Android iPhone Blackberry Windows Phone ... Android Wear Kindle Fire

  • Coccinella icon

    Coccinella

    Coccinella is a free and open-source cross-platform instant messaging client with a built-in whiteboard for improved collaboration with other people.

    Open Source Mac Windows Linux BSD

  • Tencent QQ icon

    Tencent QQ

    Tencent QQ, generally referred to as QQ, is the most popular free instant messaging computer program in Mainland China, and has over 856.2 million users. In April 2010, QQ.com ranked 10th overall in Alexas internet rankings.

    Free Mac Windows Android iPhone Windows Phone Android Tablet ... iPad Facebook

  • qutIM icon

    qutIM

    qutIM - free open-source multiprotocol ( ICQ, Jabber/GTalk/Ya.Online/LiveJournal.com, Mail.Ru, IRC ) instant messenger for Windows, Linux, MacOS X, OS/2, Symbian, Maemo/MeeGo, Solaris and *BSD.

    Open Source Mac Windows Linux S60 BSD Haiku

    • Discontinued The project seems to be no longer developed. Last versions for Windows, Mac, Linux and other platforms can be still downloaded from the official website.
  • AIM icon

    AIM

    AOL Instant Messenger is an instant messaging and presence computer program which uses the proprietary OSCAR instant messaging protocol and the TOC protocol to allow registered users to communicate in real time.HistoryAOL Instant...

    Freemium Mac Windows Web / Cloud Android iPhone Windows Mobile ... Blackberry Windows RT iPad

  • Brosix icon

    Brosix

    Brosix is a secure Instant Messaging and collaboration tool, ideal for everyday communication for business and leisure. Two different versions of Brosix give you the opportunity to choose the version best for you. » Brosix...

    Free Personal Mac Windows Linux Web / Cloud Android iPhone ... Android Tablet iPad

  • LimeChat icon

    LimeChat

    LimeChat is an IRC client for Windows, Mac OS X and iOS. Features Can connect to multiple servers in a window By key operation was rich, achieve a sense of comfortable operation Customization capabilities over the details ...

    Open Source Mac Windows iPhone iPad

  • Pinger icon

    Pinger

    Pinger lets you text and talk free with the people you care about most, anywhere on the planet. Tap a picture and you'll see all of your communications—texts, pics, calls, voicemails—all in one place. Together with millions of...

    Free Personal Mac Windows Web / Cloud Android iPhone

  • Indoona icon

    Indoona

    Indoona is the first app to communicate and share your posts with the contacts in your phonebook Features: * FREE CALLS FOREVER: indoona offers you 100 min/month of free calls to Western Europe (landlines) and Canada, China, US ...

    Freemium Mac Windows Web / Cloud Android iPhone Windows Phone

  • Camfrog icon

    Camfrog

    Free live webcam video chat room software for multiple desktop platforms including mobile platforms like iOS and Android. Make free live audio & video calls world-wide or Join live webcam chat rooms or host your own for free...

    Freemium Mac Windows Linux Android iPhone Android Tablet ... iPad Kindle Fire

  • centerim icon

    centerim

    Centerim is an command line interface chat client for the common protocols like icq, msn, aim, jabber, ...

    Open Source Mac Linux BSD

  • Paltalk icon

    Paltalk

    Paltalk is an instant messaging service that enables users to communicate via internet chat, voice and video chat. It offers chat rooms and the ability for users to create their own public virtual chat room. Free live video chat...

    Freemium Mac Windows Web / Cloud Android iPhone Kindle Fire

  • FireFloo Communicator icon

    FireFloo Communicator

    FireFloo is an instant messaging communicator combining the open XMPP standard (Jabber, GMail Chat etc.) with the echo protocol for multi-encrypted messaging. Use various methods to send chipertext over open standards like libgcrypt...

    Open Source Mac Windows Linux Android

  • Messenger for Desktop icon

    Messenger for Desktop

    A simple & beautiful app for Facebook Messenger. Chat without distractions on any Operating System.

    Open Source Mac Windows Linux

    • Bundleware Be careful during the installation: https://alternativeto.net/discussions/applications/11718/be-careful-in-the-installation/
  • 4talk Messenger icon

    4talk Messenger

    4talk IM service is a complete IM service for communicating with your phone contacts using your PC in the office or at home. You can transfer files and messages and access your correspondence from your mobile devices.

    Freemium Mac Windows Web / Cloud Android iPhone

  • BitlBee icon

    BitlBee

    BitlBee brings IM (instant messaging) to IRC clients. It's a great solution for people who have an IRC client running all the time and don't want to run an additional MSN/AIM/whatever client. BitlBee currently supports the...

    Open Source Mac Windows Linux BSD