OpenPGP

computer program for data encryption, primarily in email (PGP)

complete implementation of the OpenPGP and S/MIME standards

Enigmail is a data encryption and decryption extension for Mozilla Thunderbird and the Postbox that provides OpenPGP public key e-mail encryption and signing. Enigmail works under Microsoft Windows, Unix-like, and Mac OS X operating systems. Enigmail can operate with other mail clients compatible with PGP/MIME and inline PGP such as: Microsoft Outlook with Gpg4win package installed, Gnome Evolution, KMail, Claws Mail, Gnus, Mutt. Its cryptographic functionality is handled by GNU Privacy Guard.

mechanism for authenticating cryptographic keys

event where people sign each other's PGP key

Mailfence is a Belgian encrypted email service with a focus on security and privacy that offers OpenPGP based end-to-end encryption and digital signatures for usage in emails. It was launched in November 2013 by ContactOffice Group, which has been operating an online collaboration suite since 1999.

Gpg4win is an email and file encryption package for most versions of Microsoft Windows and Microsoft Outlook, which utilises the GnuPG framework for symmetric and public-key cryptography, such as data encryption, digital signatures, hash calculations etc.

GNOME front-end application for managing PGP and SSH keys

REDIRECT Pretty Good Privacy#OpenPGP

Keybase is a key directory that maps social media identities to encryption keys (including, but not limited to PGP keys) in a publicly auditable manner. Additionally it offers an end-to-end encrypted chat and cloud storage system, called Keybase Chat and the Keybase Filesystem respectively. Files placed in the public portion of the filesystem are served from a public endpoint, as well as locally from a filesystem union-mounted by the Keybase client.

OpenKeychain is a free and open-source mobile app for the Android operating system that provides strong, user-based encryption which is compatible with the OpenPGP standard. This allows users to encrypt, decrypt, sign, and verify signatures for text, emails, and files. The app allows the user to store the public keys of other users with whom they interact, and to encrypt files such that only a specified user can decrypt them. In the same manner, if a file is received from another user and its public keys are saved, the receiver can verify the authenticity of that file and decrypt it if necessa

Hushmail is an encrypted proprietary web-based email service offering PGP-encrypted e-mail and vanity domain service. Hushmail uses OpenPGP standards. If public encryption keys are available to both recipient and sender (either both are Hushmail users or have uploaded PGP keys to the Hush keyserver), Hushmail can convey authenticated, encrypted messages in both directions.

WinPT or Windows Privacy Tray is frontend to the GNU Privacy Guard (GnuPG) for the Windows platform. Released under GPL, it is compatible with OpenPGP compliant software.