GnuPG (GNU Privacy Guard) is the free, GPL-licensed implementation of the OpenPGP standard. A command-line tool for Linux, macOS, and Windows, it encrypts and signs files and email, and manages public-key directories.
Official website gnupg.org
Our take
GnuPG is the bedrock of open-source encryption, trusted by journalists, sysadmins, and security researchers for decades, with an active development team based in Germany and a record of prompt security advisories. The catch is the interface: the CLI is powerful but unforgiving for newcomers, and the OpenPGP web-of-trust model demands key management discipline. Pick GnuPG if you are comfortable at a terminal and need a proven, auditable foundation; pair it with a GUI frontend like Kleopatra or GPG Suite if you are not.
GitHub at a glance
gpg/gnupg
Stars
949
+ 0 this week
Last commit
2d ago
healthy
License
GPL-3.0
Stars, last 10d
Listed in
GnuPG alternatives
VERNAM A free, fully client-side file encryptor that runs in your browser. Drop in any file, set or generate a passphrase, and it seals the result into its own .vrn format. Nothing is ever uploaded, and it works offline.
VeraCrypt It can create a virtual encrypted disk that works just like a regular disk but within a file. It can also encrypt a partition or the entire storage device with pre-boot…
Cryptomator Cryptomator encrypts your data quickly and easily. Afterwards you upload them protected to a cloud service.
PrivacyNotes Zero-knowledge notes, tasks, files, passwords and journal secured by a single 12-word recovery phrase, with no email or password required. The crypto core and database schema are published for audit. No subscription model.
7-Zip File archiver with a high compression ratio and built-in encryption functionality.
Gpg4win Gpg4win is the official Windows installer for GnuPG, bundling the Kleopatra certificate manager and GpgOL for Outlook integration. It provides OpenPGP and S/MIME encryption for files and email on Windows.
GnuPG license, in plain English
GPL-3.0 Strong copyleft
Free to use and modify, but anything you distribute that is built on it must also be open under the same license.
Permits
- Commercial use
- Modification
- Distribution
- Patent use
- Private use
Requires
- Disclose source
- Same license
- State changes
- License and copyright notice
Does not provide
- Liability cover
- Warranty
Why it matters: Strong copyleft keeps every distributed version open. A vendor cannot fold this into a closed product and ship it without releasing their changes.
Plain-language summary of the project's license, not legal advice. Read the full text for the exact terms.