diff --git a/spacetaxi.js b/spacetaxi.js
index 8b8ff3c..9388e31 100644
--- a/spacetaxi.js
+++ b/spacetaxi.js
@@ -65,11 +65,23 @@ function create_star()
 }
 
 function check_password(e) {
-    // To-Do?
+    password = e.target.value;
+    
+    if (password.length > 12)
+    {
+        alert("Passwort darf höchstens 12 Zeichen lang sein!");
+        document.querySelector("form").password.value = "";
+    }
 }
 
 function check_username(e) {
-    // To-Do?
+    username = e.target.value;
+    
+    if (username.length > 8)
+    {
+        alert("Username darf höchstens 8 Zeichen lang sein!");
+        document.querySelector("form").username.value = "";
+    }
 }
 
 function check_after_submitting(e)