diff --git a/README.md b/README.md
index 18d375f..b24083a 100644
--- a/README.md
+++ b/README.md
@@ -345,7 +345,7 @@ A few examples of piecing together commands:
 
 - `factor`: factor integers
 
-- `gpg`: encrypt and sign files
+- [`gpg`](https://gnupg.org/): encrypt and sign files
 
 - `toe`: table of terminfo entries