Kannel

Free plan

What the maker publishes

Download

The download page identifies version 1.4.5 as the stable release intended for production systems and version 1.5.0 as the development release. source

Founded

1999 source

Free plan

Yes source

Inbound webhooks

Yes source

Integration

Kannel provides an HTTP interface for administration and sending SMS, and its guide documents HTTP and SMPP SMSC connections. source

License

The Kannel Software License permits redistribution and modification of source and binary forms subject to its stated conditions. source

Messaging

The user guide describes support for mobile-originated and mobile-terminated SMS messages. source

Platform

Kannel is mainly developed on Linux and the overview says it should be fairly easy to port to other Unix-like systems. source

Product

Kannel is an open-source WAP and SMS gateway for mobile internet connectivity, WAP Push, and SMS messaging. source

Project history

The project site says Wapit Ltd. founded Kannel in June 1999 and that the project is coordinated by members of the Kannel Group. source

Security

The user guide documents SSL support for HTTP client and server communication, and SSL-enabled SMPP connections. source

SMSC limits

The user guide cautions that SMSC drivers do not all support the same features and that many checklist entries are marked not tested. source

SMS protocols

The FAQ lists support for CIMD 1.3 and 2.0, SMPP 3.4, UCP/EMI 4.0, SEMA SMS2000 OIS, and AT-protocol modems and phones. source

SMS use

It links HTTP-based services to SMS centers and provides a unified interface for sending SMS messages. source

Support

The project directs users to its mailing lists for contact information and the developer mailing list for development discussion and patches. source

Two-way SMS

Yes source

WAP features

The gateway translates WAP requests to HTTP and compresses WML pages for delivery to phones. source

WAP Push

The user guide lists support for WAP Push SI and SL. source

Checked against the maker's pages on 7 Oct 2026.