This is the complete list of software we know to work or once used to work with GnuPG. The header line indicates the supported operating systems and the type of the software:

GUI

A graphical user interface for GnuPG

MUA

A Mail User Agent (mail program) or a Plugin for MUA

CHAT

A chat client

INST

An installer package

LIB

Software to help writing programs with GnuPG support.

SRV

Software for use on servers.

MISC

Other types of software

The flag Active indicates that we know that this software is actively maintained. Obsolete mean that the software is not anymore useful.

Is a very nice GTK+ based MUA with full support for GnuPG.

Cryptophane is an easy-to-use application for MS Windows. It allows users to encrypt, sign, decrypt, and perform key maintenance without having to deal with GnuPG's command-line interface.

Unices without a /dev/random should download and install this Entropy Gathering Daemon.

Mozilla Firefox extension for HTTP+OpenPGP support (see mod_auth_openpgp).

Is a plug-in for Mozilla's Thunderbird mailer.

Is a plugin for the proprietary Eudora MUA.

Is a catch all MUA application for the GNOME desktop.

Is a Tcl/Tk based MUA.

ez-pine-gpg is a set of scripts that allows beginners and experts to use gpg with Pine. There are plenty of other applications that allow gpg to be used with Pine: this one is intended to be the best, since it merges intuitive use with powerful features. The result is an application that's not only fast and secure, but also perfect for novices and power-users alike.

Gabber is a Free and Open Source GNOME client for an instant messaging system called Jabber (XMPP). Jabber is a Free and Open Source distributed instant messaging system. It does not rely on a single server, and the protocol is well documented. Jabber allows communication with many different instant messaging systems, including ICQ and AIM.

The goal of Gajim is to provide a full featured and easy to use Jabber client. Gajim works nicely with GNOME, but does not require it to run. It is released under the GNU General Public License.

Is an outgoing mail processor, and an SMTP tunnel between the MUA and the MTA. It strongly uses the GnuPG via the GPGME interface. With this GNU tool you can encrypt or sign an outgoing mail on-the-fly.

Is a GNUStep MUA with support for GnuPG.

GnuPG Shell is a cross-platform graphical frontend for GnuPG.

This is a Java binding for GPGME library.

Aims to be the standard GnuPG graphical frontend. GPA is hosted on this site. The Windows version is part of Gpg4win.

gpg_encrypt() is a PHP function that will allow you to easily use GnuPG to encrypt data to your public PGP key and mail that encrypted data to yourself, where it can be securely decrypted with your private key. This is designed primarily for use with web-based forms but can be used to encrypt any data.

This script is able to encode/sign emails in an automatic fashion. There is also a mirror site available.

Gpg4win is an installer package for Windows with computer programs and handbooks for email and file encryption.

Is a mail program for MAC OS X. Note that only the source code is delivered without charge; a binary version requires a paid subscription.

GnuPG Made Easy is the standard library for applications to access most GnuPG functions.

A plug-in for the Windows version of Microsoft Outlook. It is part of Gpg4win.

Is a Windows program which can be used to use GnuPG with all MUAs.

GPGTools is an installer package for Mac OS X. It integrates all required modules for easy use of GnuPG on this OS. Note that only the source code is delivered without charge; a binary version requires a paid subscription.

Jaro Mail is an integrated suite of interoperable tools to manage e-mail communication in a private and efficient way, without relying too much on on-line services, in fact encouraging users to store their email locally.

Is a tool to fetch keys from keyservers.

Is a KDE frontend for GnuPG.

From the KDE desktop, it fully supports GnuPG.

This frontend is for GnuPG and old-style pgp2. It works slightly similar to Raph Levien's premail: it sits between MUA and MTA and decides based on the keyring contents whether to sign, sign/encrypt or leave an email as it is. kuvert is unix-only and designed to work for outbound emails only. It's a daemon tool and requires some form of passphrase cache. kuvert has been around (under earlier names) since about 1996.

The MacGPG project has information on using GnuPG on OS-X.

Is yet another set of scripts to use GnuPG with Pine.

For Emacs. You may need the latest patches until there is a new release of Mailcrypt.

A MUA with support for GnuPG.

Has support for GnuPG.

Apache module for HTTP+OpenPGP support (see also Enigform).

Is an advanced non-graphical MUA with complete MIME and GnuPG/PGP support.

The Not-So-Bad Distribution system.

Is a web based mailer to send encrypted messages.

PGG is a complete PGP signing/encrypting solution provided from scratch by the Gnus development team. It deserves the same than mailcrypt but it has also native MIME support whereas mailcrypt does not. There is no PGG homepage at the moment, sorry.

Can be used to analyze OpenPGP data formats.

Is a Pine and procmail filter which allows one to process messages with GnuPG.

Is a comandline wrapper tool to allow the use of scripts written for PGP with GnuPG.

Is a perl script to sign HTML pages.

Secure PinEntry Dialog. This is required by GnuPG-2 and part of all installers.

Is what the name says.

Psi is a free and crossplatform client for connecting to the Jabber network. It supports multiple accounts, group chat, Unicode, and strong security (TLS and GnuPG).

Scribe is a small and fast email client that lets you send, receive and manage email without fuss. Scribe comes with a plugin that calls GnuPG.

Is another webmail client.

Is a GNOME frontend for GnuPG.

Is a versatile HTML form handler.

A gpg plugin for the popular Squirrelmail web mail server.

Is a very nice GTK+ based MUA with full support for GnuPG.

Tkabber is a free client for an instant messaging system called Jabber (aka XMPP). It is written in Tcl/Tk and supports many features like support of unicode, ssl support, http proxy, file transfers and support of multi-user conference protocol.

Is another program to use GnuPG with Pine.

wija is a free and cross-platform Jabber/XMPP client written in Java, with built-in GnuPG key rings management GUI. Its extended protocols allow users to encrypt chat and multi-user chat as well as encrypting/signing messages and signing presence of the user. It is multilingual and runs on GNU/Linux, Mac OS X and Windows.

WinGPG is a tray-based classical Windows application, Windows NT Explorer shell extension, and a classic GPGv2 distribution (it uses the cryptography from the official site without making any modifications).

Is the X application panel and filemanager.

Works with GnuPG.