diff --git a/http_cache/expiration.rst b/http_cache/expiration.rst
index d30893b58fe..ae436e631ee 100644
--- a/http_cache/expiration.rst
+++ b/http_cache/expiration.rst
@@ -34,7 +34,7 @@ additional directives):
 
 .. code-block:: text
 
-    Cache-Control: public, maxage=600
+    Cache-Control: public, max-age=600
 
 .. note::