diff --git a/docs/TODO b/docs/TODO
index d537649d1bdfa3cf22b480ade537b166614162d2..e49d7caa60ef76f357f7aeb1ad83cca849bb877a 100644
--- a/docs/TODO
+++ b/docs/TODO
@@ -772,7 +772,7 @@ that doesn't exist on the server, just like --ftp-create-dirs.
  information that is stored in HTTP headers (RFC 6249). Theoretically this could
  also be supported with the --metalink option.
 
- See http://tools.ietf.org/html/rfc6249
+ See https://tools.ietf.org/html/rfc6249
 
  See also https://lists.gnu.org/archive/html/bug-wget/2015-06/msg00034.html for
  an implematation of this in wget.