diff --git a/index.html b/index.html
index 76bb91b..43f516c 100644
--- a/index.html
+++ b/index.html
@@ -5,6 +5,21 @@
     <link rel="icon" type="image/svg+xml" href="/favicon.svg" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <title>Carleton CS Course Graph</title>
+    <meta
+      name="description"
+      content="Explore Carleton CS course prerequisites and plan your degree term by term."
+    />
+    <meta name="theme-color" content="#ef1a1a" />
+    <meta property="og:type" content="website" />
+    <meta property="og:title" content="Carleton CS Course Graph" />
+    <meta
+      property="og:description"
+      content="Explore Carleton CS course prerequisites and plan your degree term by term."
+    />
+    <!-- TODO: replace with the real deployed URL — must be absolute (incl. https://) -->
+    <meta property="og:url" content="https://TODO.example.com/" />
+    <!-- TODO: create a preview image (e.g. public/preview.png) and use its absolute deployed URL -->
+    <meta property="og:image" content="https://TODO.example.com/preview.png" />
     <script>
       // Decode the ?/ redirect injected by 404.html (GitHub Pages SPA trick).
       // Runs before React boots so BrowserRouter sees the correct pathname.