diff --git a/data/string-formats.yaml b/data/string-formats.yaml
index 0b7a9b45..2adf6fdb 100644
--- a/data/string-formats.yaml
+++ b/data/string-formats.yaml
@@ -60,4 +60,4 @@ mx-mxc-uri:
 
 uri:
   title: URI
-  url: http://tools.ietf.org/html/rfc3986
+  url: https://datatracker.ietf.org/doc/html/rfc3986