diff --git a/lib/xenu_nntp/session.py b/lib/xenu_nntp/session.py
index c79bf6d..aba0d90 100644
--- a/lib/xenu_nntp/session.py
+++ b/lib/xenu_nntp/session.py
@@ -646,7 +646,7 @@ class Session(Connection):
         def f(s: str):
             return s.replace('\t', ' ').replace('\r', '').replace('\n', ' ').replace('\0', '')
 
-        int_bytes = len(bytes(message.content, 'utf-8'))
+        int_bytes = len(message.content.encode('utf-8'))
         int_lines = message.body.count('\n') - 2
 
         def _or(a, b):