diff --git a/README.md b/README.md
index 7822aa0..86eb72b 100644
--- a/README.md
+++ b/README.md
@@ -101,6 +101,7 @@ All are optional, JWT_SECRET is recommended to be set.
 | LANGUAGE                     | en                                                 | Language to format date strings in, specified as a [BCP 47 language tag](https://en.wikipedia.org/wiki/IETF_language_tag)                                     |
 | UNAUTHENTICATED_USER_SHARING | false                                              | Shares conversion history between all unauthenticated users                                                                                                   |
 | MAX_CONVERT_PROCESS          | 0                                                  | Maximum number of concurrent conversion processes allowed. Set to 0 for unlimited.                                                                            |
+| PORT                         | 3000                                               | Application listen port                                                                                                                                       |
 
 ### Docker images