diff --git a/legendary/utils/cli.py b/legendary/utils/cli.py
index c0fe14a..ff8eb6e 100644
--- a/legendary/utils/cli.py
+++ b/legendary/utils/cli.py
@@ -84,7 +84,7 @@ def strtobool(val):
     val = val.lower()
     if val in ('y', 'yes', 't', 'true', 'on', '1'):
         return 1
-    elif val in ('n', 'no', 'f', 'false', 'off', '0'):
+    elif val in ('n', 'no', 'f', 'false', 'off', '0', ''):
         return 0
     else:
         raise ValueError("invalid truth value %r" % (val,))