diff --git a/classes/Controller/DownloadController.php b/classes/Controller/DownloadController.php
index dd3e46f..834f48d 100644
--- a/classes/Controller/DownloadController.php
+++ b/classes/Controller/DownloadController.php
@@ -21,6 +21,7 @@ use Alltube\Stream\PlaylistArchiveStream;
 use Alltube\Stream\YoutubeStream;
 use Slim\Http\Request;
 use Slim\Http\Response;
+use Slim\Http\StatusCode;
 use Slim\Http\Stream;
 
 /**
@@ -203,8 +204,8 @@ class DownloadController extends BaseController
             $response = $response->withHeader('Content-Length', $stream->getHeader('Content-Length'));
             $response = $response->withHeader('Accept-Ranges', $stream->getHeader('Accept-Ranges'));
             $response = $response->withHeader('Content-Range', $stream->getHeader('Content-Range'));
-            if ($stream->getStatusCode() == 206) {
-                $response = $response->withStatus(206);
+            if ($stream->getStatusCode() == StatusCode::HTTP_PARTIAL_CONTENT) {
+                $response = $response->withStatus(StatusCode::HTTP_PARTIAL_CONTENT);
             }
 
             if (isset($this->video->downloader_options->http_chunk_size)) {
diff --git a/classes/Controller/FrontController.php b/classes/Controller/FrontController.php
index 2b6109a..9526c0c 100644
--- a/classes/Controller/FrontController.php
+++ b/classes/Controller/FrontController.php
@@ -11,6 +11,7 @@ use Alltube\Library\Exception\AlltubeLibraryException;
 use Alltube\Library\Exception\WrongPasswordException;
 use Alltube\Locale;
 use Exception;
+use Slim\Http\StatusCode;
 use Symfony\Component\ErrorHandler\ErrorRenderer\HtmlErrorRenderer;
 use Throwable;
 use Psr\Container\ContainerInterface;
@@ -142,7 +143,7 @@ class FrontController extends BaseController
             ]
         );
 
-        return $response->withStatus(403);
+        return $response->withStatus(StatusCode::HTTP_FORBIDDEN);
     }
 
     /**
@@ -256,7 +257,7 @@ class FrontController extends BaseController
             ]
         );
 
-        return $response->withStatus(500);
+        return $response->withStatus(StatusCode::HTTP_INTERNAL_SERVER_ERROR);
     }
 
     /**
diff --git a/classes/Controller/JsonController.php b/classes/Controller/JsonController.php
index 9e37cc2..1247c6b 100644
--- a/classes/Controller/JsonController.php
+++ b/classes/Controller/JsonController.php
@@ -9,6 +9,7 @@ namespace Alltube\Controller;
 use Alltube\Library\Exception\AlltubeLibraryException;
 use Slim\Http\Request;
 use Slim\Http\Response;
+use Slim\Http\StatusCode;
 
 /**
  * Controller that returns JSON.
@@ -38,7 +39,7 @@ class JsonController extends BaseController
             return $response->withJson($this->video->getJson());
         } else {
             return $response->withJson(['error' => 'You need to provide the url parameter'])
-                ->withStatus(400);
+                ->withStatus(StatusCode::HTTP_BAD_REQUEST);
         }
     }
 }