diff --git a/.env.example b/.env.example
index dc2fe20..9093db1 100644
--- a/.env.example
+++ b/.env.example
@@ -11,6 +11,7 @@
 # The debug console executes Python on the host machine. Keep it true on your
 # own laptop for hot reloading; set it false on anything anyone else can reach.
 DASH_DEBUG=true
+PORT=5050
 
 
 # ---------------------------------------------------------------------------
diff --git a/src/app.py b/src/app.py
index 26b472e..c8db985 100644
--- a/src/app.py
+++ b/src/app.py
@@ -24,6 +24,7 @@
 
 # Load environemnt variables into globals
 DASH_DEBUG = os.getenv("DASH_DEBUG", "true").strip().lower() == "true"
+PORT = int((os.getenv("PORT", "5050") or "5050").strip())
 MOCK_PLATFORM_HEADER = int(os.getenv("MOCK_PLATFORM_HEADER", "0") or 0)
 MOCK_PLATFORM_SPACER = int(os.getenv("MOCK_PLATFORM_SPACER", "20") or 20)
 LOG_MEMORY = os.getenv("LOG_MEMORY", "false").strip().lower() == "true"
@@ -134,5 +135,5 @@ def highlight_active_tab(pathname):
 
 
 if __name__ == "__main__":
-    # Run the app. Set DASH_DEBUG in .env to toggle debug mode.
-    app.run(debug=DASH_DEBUG)
+    # Run the app. Set DASH_DEBUG and PORT in .env to configure.
+    app.run(debug=DASH_DEBUG, port=PORT)