diff --git a/src/api/api_lib.c b/src/api/api_lib.c
index e3752885..86df911e 100644
--- a/src/api/api_lib.c
+++ b/src/api/api_lib.c
@@ -119,19 +119,6 @@ netconn_delete(struct netconn *conn)
   return ERR_OK;
 }
 
-/**
- * Get the type of a netconn (as enum netconn_type).
- *
- * @param conn the netconn of which to get the type
- * @return the netconn_type of conn
- */
-enum netconn_type
-netconn_type(struct netconn *conn)
-{
-  LWIP_ERROR("netconn_type: invalid conn", (conn != NULL), return NETCONN_INVALID;);
-  return conn->type;
-}
-
 /**
  * Get the local or remote IP address and port of a netconn.
  * For RAW netconns, this returns the protocol instead of a port!
diff --git a/src/include/lwip/api.h b/src/include/lwip/api.h
index 8a116597..323ac1b6 100644
--- a/src/include/lwip/api.h
+++ b/src/include/lwip/api.h
@@ -168,7 +168,8 @@ struct
 netconn *netconn_new_with_proto_and_callback(enum netconn_type t, u8_t proto,
                                    netconn_callback callback);
 err_t             netconn_delete  (struct netconn *conn);
-enum netconn_type netconn_type    (struct netconn *conn);
+/** Get the type of a netconn (as enum netconn_type). */
+#define netconn_type(conn) (conn->type)
 
 err_t             netconn_getaddr (struct netconn *conn,
                                    struct ip_addr *addr,