ejabberd is an open-source XMPP, MQTT, and SIP server built for massive scale. See 2026 features, Community vs Business Edition pricing, and top alternatives.
ejabberd is an open-source, Erlang-based server that implements the XMPP messaging protocol along with MQTT and SIP support, making it a flexible backend for chat, presence, IoT messaging, and voice signaling. It was started in 2002 by Alexey Shchepin and has been maintained since 2005 by ProcessOne, a French company founded specifically to support the project commercially.
The server is best known for its role in real-time messaging infrastructure at massive scale, having influenced WhatsApp's early architecture, powered a modified deployment behind Facebook's original chat feature, and today running the Nintendo Switch friend and communication network.
ejabberd supports the full range of XMPP extension protocols including multi-user chat rooms, publish-subscribe messaging, message archive management, and mobile push notifications, all built on Erlang/OTP's distributed, fault-tolerant runtime. Clustering allows a single node to handle roughly a million to two million concurrent connections, with horizontal scaling across nodes for larger deployments.
Beyond chat, ejabberd includes a native MQTT broker for IoT device messaging and a SIP proxy for voice signaling, letting a single server handle multiple real-time communication protocols. It can be extended with custom Erlang or Lua modules and integrates with external SQL databases for large-scale data storage.
The Community Edition is free and open source under the GPLv2, with full production functionality and no licensing fees, though it does not include a formal support contract from ProcessOne.
The Business Edition adds enterprise features like Long-Term Support releases, enhanced performance modules, and direct SLAs with 24/7 support options, while Fluux offers a fully managed, hosted ejabberd cloud. Both are custom-priced and require contacting ProcessOne directly for a quote.
Yes, the Community Edition is fully open source under the GPLv2 and can be self-hosted in production at no licensing cost. Paid Business Edition and Fluux cloud options add enterprise support and managed hosting.
ejabberd primarily implements XMPP for chat and presence, and also includes native MQTT broker support for IoT and SIP support for voice signaling.
A single ejabberd node can support roughly one to two million concurrently connected users, with clustering across multiple nodes enabling much larger deployments.
ejabberd was started in 2002 by Alexey Shchepin and has been maintained since 2005 by the French company ProcessOne, which also offers commercial Business Edition and Fluux hosted plans.
ejabberd is widely reported to have influenced WhatsApp's original server architecture in its early years, though WhatsApp later built its own custom messaging infrastructure.
Community Edition is the free, open-source core server. Business Edition adds Long-Term Support releases, enhanced performance modules, mobile push at scale, and direct ProcessOne SLAs, priced on a custom basis.