diff --git a/doc/api.rst b/doc/api.rst
index 95e558ae..347dc649 100644
--- a/doc/api.rst
+++ b/doc/api.rst
@@ -109,7 +109,7 @@ Utilities
    :protected-members:
    :members:
 
-System Errors
+System errors
 =============
 
 .. doxygenclass:: fmt::SystemError