PGP (Pretty Good Privacy)

PGP (Pretty Good Privacy) is a method of encrypting and digitally signing messages and files. The open standard is OpenPGP, implemented by tools such as GnuPG. Each user has a public key to share and a private key to guard.

Why it matters

Used with email, PGP can give end-to-end encryption: only the intended recipient can decrypt. Unlike S/MIME, which relies on certificate authorities, PGP uses a web of trust and key servers, where people verify each other's key fingerprints. It is favoured by journalists, developers (who sign software releases and Git commits) and privacy-conscious groups. Its drawbacks are usability, key management and the fact that subject lines and metadata are generally not encrypted.

Example

Typical GnuPG commands:

gpg --full-generate-key
gpg --armor --export jane@example.com > jane.pub.asc
gpg --encrypt --recipient bob@example.com --armor message.txt
gpg --decrypt message.txt.asc

Bob must first import Jane's public key and confirm its fingerprint through another channel, such as a phone call.

Common mistakes

• Sharing the private key or keeping it unprotected by a passphrase.
• Trusting a public key from a server without verifying the fingerprint.
• Forgetting to create and store a revocation certificate.

Related

• S/MIME
• Public Key
• Private Key
• Digital Signature

This page is general information written by our editorial team and updated when documentation changes. Servers and providers differ, so test changes safely first. See our editorial policy and disclaimer.