Welcome to GnuTLS project pages

  • Overview

    GnuTLS is a secure communications library implementing the SSL, TLS and DTLS protocols and technologies around them. It provides a simple C language application programming interface (API) to access the secure communications protocols as well as APIs to parse and write X.509, PKCS #12, and other required structures.

    The project strives to provide a secure communications back-end, simple to use and integrated with the rest of the base Linux libraries. A back-end designed to work and be secure out of the box, keeping the TLS and PKI complexity outside the applications.

  • Features
  • License

    The core library licensed under the GNU Lesser General Public License version 2.1 (LGPLv2.1+). The LGPL license is compatible with a wide range of free licenses, and even permit you to use GnuTLS in non-free proprietary programs.

For more information on GnuTLS features, see the wikipedia article comparing different TLS implementations.

News flashes  

Released GnuTLS 3.6.3 of the next branch with support for TLS1.3, and, GnuTLS 3.5.19, GnuTLS 3.3.30 which are bug-fix releases on the stable and previous stable branches.


A heads-up with the most prominent GnuTLS changes for TLS 1.3 published in Nikos' blog.


Released GnuTLS 3.6.2, GnuTLS 3.5.18, and GnuTLS 3.3.29 which are bug-fix releases on the next, stable and previous stable branches.


Released GnuTLS 3.5.17 which is a bug-fix release on the current stable branch.