Quick reference for gpg (GNU Privacy Guard), used for encryption, signing, and key management following the OpenPGP standard.

Key management

• gpg --full-generate-key – interactive key generation.
• gpg --list-keys / gpg --list-secret-keys – list public/secret keys.
• gpg --delete-key <ID> – delete a public key.
• gpg --delete-secret-key <ID> – delete a secret key.

Export / import keys

• gpg --export -a <ID> > public.asc – export public key (ASCII armored).
• gpg --export-secret-keys -a <ID> > secret.asc – export secret key (backup only).
• gpg --import public.asc – import a key.
• gpg --recv-key <ID> – fetch from keyserver (if configured).

Encrypt / decrypt

• gpg -e -r <recipient> file – encrypt to recipient’s key.
• gpg -d file.gpg – decrypt a file.
• echo "secret" | gpg -e -r <recipient> > secret.txt.gpg – encrypt from stdin.

Signing

• gpg -s file – create a binary signature.
• gpg -sa file – create an ASCII-armored signature.
• gpg --clear-sign file – cleartext sign (visible content + signature block).
• gpg --verify file.sig file – verify a detached signature.

Trust and IDs

• gpg --edit-key <ID> – manage key, set trust, add UIDs, etc.
• gpg --fingerprint <ID> – show key fingerprint.
• Verify fingerprints out-of-band (in person, chat, etc.) before trusting.

Tips

• Use a modern key type (ed25519 or cv25519) where available.
• Back up your secret key and revoke certificate somewhere safe.
• Combine gpg with pass and git for a simple password manager.