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GNU Privacy Guard (GnuPG or GPG) is a free-software replacement for Symantec's PGP cryptographic software suite.

A secure solution for file and email encryption.

Free software for checking signed and sealed documents and time stamps

Sign your PDF documents with ease

Free PGP Encryption Software

A modern, cross-platform, open-source GUI for OpenPGP encryption.

Automatic and centrally managed email signatures for all staff on all devices.

Synchronize signatures directly with the user's Outlook on Windows.

Sign your documents digitally

Alipay key tool

Detect It Easy, or abbreviated DIE is a program for determining types of files.