diff --git a/hreflang.module b/hreflang.module
index 362e1ad..1572884 100644
--- a/hreflang.module
+++ b/hreflang.module
@@ -18,6 +18,8 @@ function hreflang_page_build(&$page) {
   if (empty($links->links)) {
     return;
   }
+	// Identify the default language.
+  $default_code = language_default('language');
   foreach ($links->links as $langcode => $link) {
     // Content translation module may unset the href attribute.
     if (!isset($link['href'])) {
@@ -33,6 +35,18 @@ function hreflang_page_build(&$page) {
       'rel' => 'alternate',
       'hreflang' => $link['attributes']['hreflang'],
     );
+		// Indicate the default language.
+    if ($langcode == $default_code) {
+      $default_attributes = array(
+          '#tag' => 'link',
+          '#attributes' => array(
+              'href' => url($link['href'], $link),
+              'rel' => 'alternate',
+              'hreflang' => 'x-default',
+          )
+      );
+      drupal_add_html_head($default_attributes, 'alternate');
+    }
     drupal_add_html_head_link($attributes);
   }
 }