diff --git a/debian/copyright b/debian/copyright
index d32a3fb..c148530 100644
--- a/debian/copyright
+++ b/debian/copyright
@@ -1,4 +1,4 @@
-Format: http://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
+Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
 Upstream-Name: clzip
 Upstream-Contact: lzip-bug@nongnu.org
 Source: http://download.savannah.gnu.org/releases/lzip/