diff --git a/ariadne/services/mailu.py b/ariadne/services/mailu.py
index 007f372..dd03f6f 100644
--- a/ariadne/services/mailu.py
+++ b/ariadne/services/mailu.py
@@ -19,6 +19,7 @@ logger = get_logger(__name__)
 MAILU_ENABLED_ATTR = "mailu_enabled"
 MAILU_EMAIL_ATTR = "mailu_email"
 MAILU_APP_PASSWORD_ATTR = "mailu_app_password"
+BCRYPT_MAX_PASSWORD_BYTES = 72
 
 
 @dataclass(frozen=True)
@@ -96,7 +97,7 @@ def _domain_matches(email: str) -> bool:
 
 
 def _password_too_long(password: str) -> bool:
-    return len(password.encode("utf-8")) > 72
+    return len(password.encode("utf-8")) > BCRYPT_MAX_PASSWORD_BYTES
 
 
 class MailuService: