diff --git a/nav.go b/nav.go
index 29c3500a..2a698172 100644
--- a/nav.go
+++ b/nav.go
@@ -200,7 +200,7 @@ func (dir *dir) sort() {
 
 			// in order to also have natural sorting with the filenames
 			// combine the name with the ext but have the ext at the front
-			return (ext1 + name1) < (ext2 + name2)
+			return ext1 < ext2 || ext1 == ext2 && name1 < name2
 		})
 	}