diff --git a/convert-pth-to-ggml.py b/convert-pth-to-ggml.py
index f87ac270c..2f91f44d1 100644
--- a/convert-pth-to-ggml.py
+++ b/convert-pth-to-ggml.py
@@ -6,6 +6,6 @@ import convert
 
 parser = argparse.ArgumentParser(description='Convert a LLaMA model checkpoint to a ggml compatible file')
 parser.add_argument('dir_model',  help='directory containing the model checkpoint')
-parser.add_argument('ftype',      help='file type (0: float32, 1: float16)', type=int, choices=[0, 1], default=1)
+parser.add_argument('ftype',      help='file type (0: float32, 1: float16)', type=int, choices=[0, 1], default=1, nargs='?')
 args = parser.parse_args()
 convert.main(['--outtype', 'f16' if args.ftype == 1 else 'f32', '--', args.dir_model])