diff --git a/Formatter/ProjectApiFormatter.php b/Formatter/ProjectApiFormatter.php
new file mode 100644
index 0000000..5520801
--- /dev/null
+++ b/Formatter/ProjectApiFormatter.php
@@ -0,0 +1,22 @@
+<?php
+
+namespace Kanboard\Plugin\Calendar\Formatter;
+
+/**
+ * Class ProjectApiFormatter
+ *
+ * @package Kanboard\Plugin\Calendar\Formatter
+ */
+class ProjectApiFormatter extends \Kanboard\Formatter\ProjectApiFormatter
+{
+    public function format()
+    {
+        $project = parent::format();
+
+        if (! empty($project)) {
+            $project['url']['calendar'] = $this->helper->url->to('CalendarController', 'project', array('project_id' => $project['id'], 'plugin' => 'Calendar'), '', true);
+        }
+
+        return $project;
+    }
+}
diff --git a/Plugin.php b/Plugin.php
index a9b88aa..3054a2a 100644
--- a/Plugin.php
+++ b/Plugin.php
@@ -4,6 +4,7 @@ namespace Kanboard\Plugin\Calendar;
 
 use Kanboard\Core\Plugin\Base;
 use Kanboard\Core\Translator;
+use Kanboard\Plugin\Calendar\Formatter\ProjectApiFormatter;
 use Kanboard\Plugin\Calendar\Formatter\TaskCalendarFormatter;
 
 class Plugin extends Base
@@ -16,6 +17,10 @@ class Plugin extends Base
             return new TaskCalendarFormatter($c);
         });
 
+        $this->container['projectApiFormatter'] = $this->container->factory(function ($c) {
+            return new ProjectApiFormatter($c);
+        });
+
         $this->template->hook->attach('template:dashboard:page-header:menu', 'Calendar:dashboard/menu');
         $this->template->hook->attach('template:project:dropdown', 'Calendar:project/dropdown');
         $this->template->hook->attach('template:project-header:view-switcher', 'Calendar:project_header/views');