diff --git a/client/index.html b/client/index.html
index e476b15..ac57f33 100644
--- a/client/index.html
+++ b/client/index.html
@@ -4,8 +4,20 @@
     <meta charset="UTF-8" />
     <link rel="icon" type="image/svg+xml" href="/logo.svg" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <meta property="og:locale" content="ja_JP" />
+    <!-- TODO: make these SEO tags dynamic if needed -->
+    <meta
+      property="og:image"
+      content="https://itsuhima.utcode.net/og-image.webp"
+    />
+    <meta property="og:site_name" content="イツヒマ" />
+    <meta
+      property="og:title"
+      content="イツヒマ - 「いつ暇？」で日程調整しよう"
+    />
     <title>イツヒマ</title>
   </head>
+
   <body style="height: 100%" class="text-gray-600">
     <div id="root" style="height: 100%"></div>
     <script type="module" src="/src/main.tsx"></script>
diff --git a/client/public/og-image.webp b/client/public/og-image.webp
new file mode 100644
index 0000000..5b74fc1
Binary files /dev/null and b/client/public/og-image.webp differ
