diff --git a/docs/patterns/javascript.rst b/docs/patterns/javascript.rst
index d58a3eb6b4..6cce7e912f 100644
--- a/docs/patterns/javascript.rst
+++ b/docs/patterns/javascript.rst
@@ -134,9 +134,7 @@ in a Flask view.
 
 In general, prefer sending request data as form data, as would be used
 when submitting an HTML form. JSON can represent more complex data, but
-unless you need that it's better to stick with the simpler format. When
-sending JSON data, the ``Content-Type: application/json`` header must be
-sent as well, otherwise Flask will return a 400 error.
+unless you need that it's better to stick with the simpler format. When sending JSON data, the ``Content-Type: application/json`` header must be sent as well, otherwise Flask will return a 415 Unsupported Media Type error.
 
 .. code-block:: javascript
 
@@ -244,8 +242,9 @@ Receiving JSON in Views
 
 Use the :attr:`~flask.Request.json` property of the
 :data:`~flask.request` object to decode the request's body as JSON. If
-the body is not valid JSON, or the ``Content-Type`` header is not set to
-``application/json``, a 400 Bad Request error will be raised.
+the body is not valid JSON, a 400 Bad Request error will be raised. If
+the ``Content-Type`` header is not set to ``application/json``, a 415
+Unsupported Media Type error will be raised.
 
 .. code-block:: python