diff --git a/README.md b/README.md
index 46f7e600..4fce7e49 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,7 @@
 [![Build Status](https://travis-ci.org/zerocracy/datum.svg?branch=master)](https://travis-ci.org/zerocracy/datum)
 [![Hits-of-Code](https://hitsofcode.com/github/zerocracy/datum)](https://hitsofcode.com/view/github/zerocracy/datum)
 
-[![Availability at SixNines](http://www.sixnines.io/b/2761)](http://www.sixnines.io/h/2761)
+[![Availability at SixNines](https://www.sixnines.io/b/2761)](https://www.sixnines.io/h/2761)
 
 Information about current project status is kept in XML and text
 files. This repository contains full list of XSD Schemas for them