diff --git a/include/event2/http.h b/include/event2/http.h
index 89175fb79e..27cbd35ede 100644
--- a/include/event2/http.h
+++ b/include/event2/http.h
@@ -53,18 +53,29 @@ struct evhttp_connection;
  */
 
 /* Response codes */
+#define HTTP_CONTINUE		100	/**< client should proceed to send */
+#define HTTP_SWITCH_PROTOCOLS	101	/**< switching to another protocol */
+#define HTTP_PROCESSING		102	/**< processing the request, but no response is available yet */
+#define HTTP_EARLYHINTS		103	/**< return some response headers */
 #define HTTP_OK			200	/**< request completed ok */
+#define HTTP_CREATED		201	/**< new resource is created */
+#define HTTP_ACCEPTED		202	/**< accepted for processing */
+#define HTTP_NONAUTHORITATIVE	203	/**< returning a modified version of the origin's response */
 #define HTTP_NOCONTENT		204	/**< request does not have content */
 #define HTTP_MOVEPERM		301	/**< the uri moved permanently */
 #define HTTP_MOVETEMP		302	/**< the uri moved temporarily */
 #define HTTP_NOTMODIFIED	304	/**< page was not modified from last */
 #define HTTP_BADREQUEST		400	/**< invalid http request was made */
+#define HTTP_UNAUTHORIZED	401	/**< authentication is required */
+#define HTTP_PAYMENTREQUIRED	402	/**< user exceeded limit on requests */
+#define HTTP_FORBIDDEN		403	/**< user not having the necessary permissions */
 #define HTTP_NOTFOUND		404	/**< could not find content for uri */
 #define HTTP_BADMETHOD		405 	/**< method not allowed for this uri */
-#define HTTP_ENTITYTOOLARGE	413	/**<  */
+#define HTTP_ENTITYTOOLARGE	413	/**< request is larger than the server is able to process */
 #define HTTP_EXPECTATIONFAILED	417	/**< we can't handle this expectation */
 #define HTTP_INTERNAL           500     /**< internal error */
 #define HTTP_NOTIMPLEMENTED     501     /**< not implemented */
+#define HTTP_BADGATEWAY		502	/**< received an invalid response from the upstream */
 #define HTTP_SERVUNAVAIL	503	/**< the server is not available */
 
 struct evhttp;