diff --git a/README.md b/README.md
index 0eddda2..cd879ee 100644
--- a/README.md
+++ b/README.md
@@ -17,6 +17,10 @@ By using [WebRTC](http://www.webrtc.org), FilePizza eliminates the initial uploa
     $ npm install
     $ npm start
 
+You can specify the port that FilePizza's HTTP server uses by setting the `PORT` environment variable:
+
+    $ env PORT=8080 npm start
+
 ## Requirements
 
 * node `0.12.x`