diff --git a/jumpapp/classes/API/Icon.php b/jumpapp/classes/API/Icon.php
index 722e3a7..71a6955 100644
--- a/jumpapp/classes/API/Icon.php
+++ b/jumpapp/classes/API/Icon.php
@@ -18,14 +18,15 @@ use \Jump\Exceptions\APIException;
 class Icon extends AbstractAPI {
 
     public function get_output(): string {
-        if (!isset($this->routeparams['siteurl']) || empty($this->routeparams['siteurl'])) {
-            throw new APIException('The siteurl query parameter is not provided or empty');
+        if (!isset($this->routeparams['siteid']) || empty($this->routeparams['siteid'])) {
+            throw new APIException('The siteid query parameter is not provided or empty');
         }
 
         $sites = new \Jump\Sites($this->config, $this->cache);
 
-        $siteurl = filter_var($this->routeparams['siteurl'], FILTER_SANITIZE_URL);
-        $site = $sites->get_site_by_url($siteurl);
+        # A site ID can contain lowercase a-z, 0-9 and the "-" (dash) character only.
+        $siteid = preg_replace("/[^a-z0-9-]/", "", $this->routeparams['siteid']);
+        $site = $sites->get_site_by_id($siteid);
 
         $imagedata =  $site->get_favicon_image_data();
 
diff --git a/jumpapp/classes/Main.php b/jumpapp/classes/Main.php
index 50a2c6b..a1d8094 100644
--- a/jumpapp/classes/Main.php
+++ b/jumpapp/classes/Main.php
@@ -34,7 +34,7 @@ class Main {
         $this->router->addRoute('/tag/<tag>', [
 			'class' => 'Jump\Pages\TagPage'
 		]);
-        $this->router->addRoute('/api/icon?siteurl=<siteurl>', [
+        $this->router->addRoute('/api/icon?siteid=<siteid>', [
 			'class' => 'Jump\API\Icon'
 		]);
         $this->router->addRoute('/api/status[/<token>]', [
diff --git a/jumpapp/templates/sites.mustache b/jumpapp/templates/sites.mustache
index 3d3469a..ebc2343 100644
--- a/jumpapp/templates/sites.mustache
+++ b/jumpapp/templates/sites.mustache
@@ -2,7 +2,7 @@
 <ul class="sites {{# altlayout}}alternate{{/ altlayout}}">
 {{# sites}}<li id="{{id}}"><a {{# newtab}}target="_blank"{{/ newtab}} rel="{{# nofollow}}nofollow {{/ nofollow}}{{# newtab}}noopener{{/ newtab}}" title="{{description}}" href="{{url}}">
     <span class="icon">
-        <img src="{{{wwwurl}}}/api/icon?siteurl={{#urlencode}}{{url}}{{/urlencode}}">
+        <img src="{{{wwwurl}}}/api/icon?siteid={{id}}">
     </span>
     <span class="name">{{name}}</span>
 </a></li>{{/ sites}}