diff --git a/Sources/Profile-View.php b/Sources/Profile-View.php
index f06637cbf0..d0a169e298 100644
--- a/Sources/Profile-View.php
+++ b/Sources/Profile-View.php
@@ -86,7 +86,7 @@ function summary($memID)
 	if (allowedTo('moderate_forum'))
 	{
 		// Make sure it's a valid ip address; otherwise, don't bother...
-		if (preg_match('/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/', $memberContext[$memID]['ip']) == 1 && empty($modSettings['disableHostnameLookup']))
+		if (filter_var($memberContext[$memID]['ip'], FILTER_VALIDATE_IP) && empty($modSettings['disableHostnameLookup']))
 			$context['member']['hostname'] = host_from_ip($memberContext[$memID]['ip']);
 		else
 			$context['member']['hostname'] = '';