diff --git a/controllers/punycode/GET.php b/controllers/punycode/GET.php
new file mode 100644
index 0000000..f705065
--- /dev/null
+++ b/controllers/punycode/GET.php
@@ -0,0 +1,12 @@
+<?php
+
+return function (array $context) {
+    if (key_exists("to", $_GET)) {
+        $context["renderer"](idn_to_ascii($_GET["to"]));
+    } elseif (key_exists("from", $_GET)) {
+        $context["renderer"](idn_to_utf8($_GET["from"]));
+    } else {
+        setStatusCode(400);
+        $context["renderer"](errorResponse("Unknown mode", "Please specify one of the following query parameters: to, from"));
+    }
+};
diff --git a/controllers/routes.php b/controllers/routes.php
index 40380d8..db75ed9 100644
--- a/controllers/routes.php
+++ b/controllers/routes.php
@@ -13,6 +13,7 @@ return function(Router $router) {
     $router->addRoute(GET, "/test", useRenderer(fromController("/test/GET")));
 
     $router->addRoute(GET, "/ipaddress", useRenderer(fromController("/ipaddress/GET")));
-
     $router->addRoute(GET, "/whois", useRenderer(fromController("/whois/GET")));
+
+    $router->addRoute(GET, "/punycode", useRenderer(fromController("/punycode/GET")));
 };
diff --git a/controllers/whois/GET.php b/controllers/whois/GET.php
index c5ef313..d8e8506 100644
--- a/controllers/whois/GET.php
+++ b/controllers/whois/GET.php
@@ -110,7 +110,7 @@ return function (array $context) {
         $result = whoisDomain($domain);
     } else {
         setStatusCode(400);
-        $result = errorResponse("Unknown mode", "Please specify one of the following query parameters: ip");
+        $result = errorResponse("Unknown mode", "Please specify one of the following query parameters: ip, domain");
     }
 
     $context["renderer"]($result);