diff --git a/app.py b/app.py
index 105030d..6ea8aed 100644
--- a/app.py
+++ b/app.py
@@ -14,9 +14,9 @@ from wtforms import HiddenField, RadioField, StringField
 from wtforms.validators import DataRequired
 
 
-def rand():
+def rand(length=30):
     """Generated random secret."""
-    return "".join(random.choices(string.ascii_uppercase + string.digits, k=N))
+    return "".join(random.choices(string.ascii_uppercase + string.digits, k=length))
 
 
 app = Flask(__name__)