diff --git a/build/sitemap/README b/build/sitemap/README
index b98b5cc48d8..a06bd58f259 100644
--- a/build/sitemap/README
+++ b/build/sitemap/README
@@ -1,5 +1,5 @@
 # Format of sitemap file is available at
-# http://www.sitemaps.org/protocol.html
+# https://www.sitemaps.org/protocol.html
 
 # To build a sitemap from urllist-bing.txt, run 
 # google-sitemapgen --config=config-bing.xml --testing