diff --git a/libopenai/constants.py b/libopenai/constants.py
index 3f827a3..c96a319 100644
--- a/libopenai/constants.py
+++ b/libopenai/constants.py
@@ -1,7 +1,7 @@
 import os
 from pathlib import Path
 
-DEFAULT_MODEL = "gpt-5.4"
+DEFAULT_MODEL = "gpt-5.5"
 
 IMAGE_EXTENSIONS = (".png", ".jpg", ".jpeg", ".webp", ".gif")
 USER_DATA_EXTENSIONS = (