diff --git a/README.md b/README.md
index 9531bf3..9306dfa 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,7 @@ This repository contains the source code of the https://3dviewer.net website. Th
 
 [![Build status](https://ci.appveyor.com/api/projects/status/exypq43a8kjby5n0?svg=true)](https://ci.appveyor.com/project/kovacsv/online3dviewer)
 [![Build Status](https://travis-ci.com/kovacsv/Online3DViewer.svg?branch=master)](https://travis-ci.com/kovacsv/Online3DViewer)
+[![Language grade: JavaScript](https://img.shields.io/lgtm/grade/javascript/g/kovacsv/Online3DViewer.svg?logo=lgtm&logoWidth=18)](https://lgtm.com/projects/g/kovacsv/Online3DViewer/context:javascript)
 
 ## Documentation