diff --git a/sites/index.php b/sites/index.php
index 1eab8a5..bcfa4c0 100644
--- a/sites/index.php
+++ b/sites/index.php
@@ -27,7 +27,8 @@
 
 	// Set the last-updated timestamp
 	// to the time the server data file was last modified.
-	$timestamp = filemtime($ROOMS_FILE);
+	$time_modified = filemtime($ROOMS_FILE);
+	$time_modified_str = date("Y-m-d H:i:s", $time_modified);
 
 ?>
 <!DOCTYPE html>
@@ -48,7 +49,7 @@
 			?>Copy Community links into the Session app!<?php
 		?>">
 		<meta name="keywords" content="session communities,session groups,session group list">
-		<meta name="modified" content="<?=date("Y-m-d H:i:s", $timestamp)?>">
+		<meta name="modified" content="<?=$time_modified_str?>">
 		<meta property="og:title" content="Click here for Session Communities">
 		<meta
 			property="og:description"
@@ -57,7 +58,7 @@
 		<meta property="og:url" content="<?=$SITE_CANONICAL_URL?>/">
 		<meta property="og:type" content="website">
 		<meta property="og:locale" content="en_US"/>
-		<meta name="timestamp" content="<?=$timestamp?>">
+		<meta name="timestamp" content="<?=$time_modified?>">
 		<noscript>
 			<style>
 				.js-only {
@@ -119,7 +120,7 @@
 
 			<hr id="footer-divider">
 
-			<aside id="summary">
+			<aside id="summary" itemid="<?=$SITE_CANONICAL_URL?>" itemtype="https://schema.org/WebSite">
 				<p id="server_summary">
 					<?=count_rooms($servers)?> unique Session Communities
 					on <?=count($servers)?> servers have been found.
@@ -127,8 +128,8 @@
 					<sup><a href="<?=$REPOSITORY_CANONICAL_URL?>/#policy" target="_blank">why?</a></sup>
 				</p>
 				<p id="last_checked">
-					Last checked <span id="last_checked_value">
-						<?=date("Y-m-d H:i:s", $timestamp)?> (UTC)
+					Last checked <span id="last_checked_value" itemprop="dateModified" value="<?=$time_modified_str?>">
+						<?=$time_modified_str?> (UTC)
 					</span>.
 				</p>
 			</aside>
