diff --git a/README.md b/README.md
index 53183ad39b40295e7c64d4fff078b015c4521996..9f747444a02a945fdfd0606b98b21a2ea00264b9 100644
--- a/README.md
+++ b/README.md
@@ -939,7 +939,7 @@ Reveal.configure({ slideNumber: 'c/t' });
 
 // You can provide a function to fully customize the number:
 Reveal.configure({ slideNumber: function() {
-	// Ignore numbering of vertical slides
+    // Ignore numbering of vertical slides
     return [ Reveal.getIndices().h ];
 }});