diff --git a/src/WebSocketsServer.h b/src/WebSocketsServer.h
index cd38fd6..538b585 100644
--- a/src/WebSocketsServer.h
+++ b/src/WebSocketsServer.h
@@ -27,7 +27,9 @@
 
 #include "WebSockets.h"
 
+#ifndef WEBSOCKETS_SERVER_CLIENT_MAX
 #define WEBSOCKETS_SERVER_CLIENT_MAX  (5)
+#endif