diff --git a/ui/src/index.html b/ui/src/index.html
index e63821220..abfb4b5bc 100644
--- a/ui/src/index.html
+++ b/ui/src/index.html
@@ -1,5 +1,5 @@
 <!doctype html>
-<html>
+<html lang="en">
 <head>
   <meta charset="utf-8">
   <title>Ui</title>
