diff --git a/index.html b/index.html
index 262aa0e..eba4756 100644
--- a/index.html
+++ b/index.html
@@ -6,6 +6,17 @@
   <meta http-equiv="X-UA-Compatible" content="IE=edge">
   <meta name="viewport" content="width=device-width, initial-scale=1.0">
   <title>Code Formatter</title>
+
+  <!-- Google tag (gtag.js) -->
+  <script async src="https://www.googletagmanager.com/gtag/js?id=G-90N1Q923X2"></script>
+  <script>
+    window.dataLayer = window.dataLayer || [];
+    function gtag() { dataLayer.push(arguments); }
+    gtag('js', new Date());
+
+    gtag('config', 'G-90N1Q923X2');
+  </script>
+
   <link rel="preconnect" href="https://fonts.googleapis.com">
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link href="https://fonts.googleapis.com/css2?family=Fira+Code&family=Roboto&display=swap" rel="stylesheet">