diff --git a/server.py b/server.py
index 39d315a..30c7562 100644
--- a/server.py
+++ b/server.py
@@ -50,7 +50,7 @@ def upload(id):
     print('processing file: ', filename)
 
     ext = os.path.splitext(filename)[1][1:].strip().lower()
-    if ext in set(['jpg', 'jpeg', 'png']):
+    if ext in set(['jpg', 'jpeg', 'png', 'PNG']):
       print('File supported moving on.')
     else:
       raise InvalidFiletype('Unsupported file type {}'.format(ext), status_code=415)