diff --git a/index.php b/index.php
index c9d6d7e..42d4dfc 100644
--- a/index.php
+++ b/index.php
@@ -48,6 +48,8 @@ if($_SERVER["REQUEST_URI"] == '/metrics' || php_sapi_name() == 'cli') {
         } else {
             $c['value'] = $output;
         }
+
+        if(is_bool($c['value'])) $c['value'] = $c['value'] ? 1 : 0;
     }
 
     $loader = new \Twig\Loader\FilesystemLoader('templates');