diff --git a/src/nano.c b/src/nano.c
index 9a7c35ea9b00a248b7fcc4e33f4729f47371307b..139a29cb627ba878cd8ba213861f77e74f6ab057 100644
--- a/src/nano.c
+++ b/src/nano.c
@@ -3643,7 +3643,7 @@ void do_output(int *kbinput, size_t kbinput_len)
 
 	/* More dangerousness fun =) */
 	current->data = charealloc(current->data,
-		current_len + key_len + 2);
+		current_len + (key_len * 2));
 
 	assert(current_x <= current_len);