Open-source messengers
18 messengers whose code is public under an OSI-approved license, rated for privacy with evidence. Picks first, then by score.
Briar Grade A
Peer-to-peer encrypted messenger for Android and desktop that syncs over Tor, Wi-Fi or Bluetooth. Messages, forums and blogs are stored only on users' devices.
GPL-3.0. Source code
Ricochet Refresh Grade A
Desktop instant messenger that runs each user as a Tor onion service and connects contacts peer to peer, hiding identity, IP address and metadata. Maintained by Blueprint for Free Speech.
LGPL-2.1 and BSD-3-Clause. Source code
Session Grade A
End-to-end encrypted messenger that uses a random Account ID instead of a phone number and sends messages through onion routing over a decentralized network of community-operated nodes. Stewarded by the Session Technology Foundation in Switzerland.
The apps are GPL-3.0, and the storage server run by network nodes is MIT. Source code
SimpleX Grade A
End-to-end encrypted messenger that has no user identifiers of any kind, not even random ones. Messages pass through relay servers that anyone can run.
AGPL-3.0. Source code
Berty Grade B
Peer-to-peer, end-to-end encrypted messenger built on IPFS by the French non-profit Berty Technologies. It needs no phone number or email and can exchange messages offline over Bluetooth and local networks.
Dual-licensed under Apache-2.0 and MIT. Source code
Cwtch Grade B
Decentralized, metadata-resistant messenger from the non-profit Open Privacy Research Society. Contacts talk peer to peer over Tor onion services, and optional group chats use untrusted servers that anyone can run.
MIT. Source code
Quiet Grade B
Peer-to-peer team chat, similar to Slack, that runs without servers: community members' devices sync messages directly over Tor. The developers warn it is not yet audited.
GPL-3.0. Source code
Conversations Grade B
XMPP (Jabber) client for Android that works with any standard XMPP server, with OMEMO end-to-end encryption on by default for one-to-one and private group chats.
GPL-3.0, and it works with open-source XMPP servers such as Prosody and ejabberd. Source code
Tox & qTox client Grade B
Peer-to-peer encrypted messaging protocol with no central servers, and qTox, its desktop client for chat, voice, video and file transfer. qTox is now maintained by the TokTok project after the original repository was archived.
GPL-3.0. Source code
Dino Grade B
Desktop XMPP (Jabber) client for Linux built with GTK, with group chats, file transfers, and voice and video calls. OMEMO end-to-end encryption is on by default for one-to-one and private group chats.
GPL-3.0, and it works with open-source XMPP servers. Source code
Molly Grade B
Independent fork of the Signal Android app that connects to the Signal network and adds database encryption with a passphrase, UnifiedPush notifications and a Molly-FOSS build without proprietary Google components.
AGPL-3.0, and it uses the open-source Signal server. Source code
OpenPGP Grade B
Open standard for public-key encryption and signing of messages and files, defined in RFC 9580. It adds end-to-end encryption to existing channels such as email, through implementations like GnuPG.
Open IETF standard with open source implementations such as GnuPG (GPL-3.0). Source code
Signal Grade B
End-to-end encrypted messenger for text, voice and video calls, and groups, built on the Signal Protocol. Run by the non-profit Signal Foundation.
AGPL-3.0. Source code
XMPP Grade B
XMPP, also known as Jabber, is an open standard for federated instant messaging maintained by the XMPP Standards Foundation, with many independent clients and servers.
Open standard (RFC 6120) with many open source clients and servers. Source code
Jami Grade B
Peer-to-peer encrypted messenger from the GNU project for text, audio and video calls, screen sharing and conferences, with apps for desktop and mobile.
GPL-3.0. Source code
Gajim Grade C
Desktop XMPP (Jabber) client for Linux, Windows and macOS that works with any standard XMPP server, with group chats, file transfer and optional OMEMO or OpenPGP end-to-end encryption.
GPL-3.0, and it works with open-source XMPP servers. Source code
Wire Grade C
End-to-end encrypted messenger and team collaboration app from Switzerland, with chats, calls and file sharing using Proteus and MLS. Accounts use an email address, and organizations can self-host federated backends.
The server is AGPL-3.0 and the apps are GPL-3.0. Source code
Matrix Grade D
Open standard and federated network for real-time chat and calls, with end-to-end encryption through the Olm and Megolm protocols. Anyone can run a homeserver, and many clients such as Element support it.
Apache-2.0. Source code
Compare all 27 messengers, open source or not.