diff --git a/src/Wallabag/CoreBundle/Controller/TagController.php b/src/Wallabag/CoreBundle/Controller/TagController.php
index acc8b8908..0063ec54a 100644
--- a/src/Wallabag/CoreBundle/Controller/TagController.php
+++ b/src/Wallabag/CoreBundle/Controller/TagController.php
@@ -11,6 +11,7 @@ use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\Routing\Annotation\Route;
+use Symfony\Contracts\Translation\TranslatorInterface;
 use Wallabag\CoreBundle\Entity\Entry;
 use Wallabag\CoreBundle\Entity\Tag;
 use Wallabag\CoreBundle\Form\Type\NewTagType;
@@ -39,7 +40,7 @@ class TagController extends AbstractController
      *
      * @return Response
      */
-    public function addTagFormAction(Request $request, Entry $entry)
+    public function addTagFormAction(Request $request, Entry $entry, TranslatorInterface $translator)
     {
         $form = $this->createForm(NewTagType::class, new Tag());
         $form->handleRequest($request);
@@ -48,7 +49,13 @@ class TagController extends AbstractController
         $tagsExploded = explode(',', $tags);
 
         // avoid too much tag to be added
-        if (\count($tagsExploded) >= 5 || \strlen($tags) >= NewTagType::MAX_LENGTH) {
+        if (\count($tagsExploded) >= NewTagType::MAX_TAGS || \strlen($tags) >= NewTagType::MAX_LENGTH) {
+            $message = $translator->trans('flashes.tag.notice.too_much_tags', [
+                '%tags%' => NewTagType::MAX_TAGS,
+                '%characters%' => NewTagType::MAX_LENGTH,
+            ]);
+            $this->addFlash('notice', $message);
+
             return $this->redirect($this->generateUrl('view', ['id' => $entry->getId()]));
         }
 
diff --git a/src/Wallabag/CoreBundle/Form/Type/NewTagType.php b/src/Wallabag/CoreBundle/Form/Type/NewTagType.php
index 60a478548..adff45cc2 100644
--- a/src/Wallabag/CoreBundle/Form/Type/NewTagType.php
+++ b/src/Wallabag/CoreBundle/Form/Type/NewTagType.php
@@ -12,6 +12,7 @@ use Wallabag\CoreBundle\Entity\Tag;
 class NewTagType extends AbstractType
 {
     public const MAX_LENGTH = 40;
+    public const MAX_TAGS = 5;
 
     public function buildForm(FormBuilderInterface $builder, array $options)
     {
diff --git a/translations/messages.en.yml b/translations/messages.en.yml
index de5483b39..30c925189 100644
--- a/translations/messages.en.yml
+++ b/translations/messages.en.yml
@@ -683,6 +683,7 @@ flashes:
         notice:
             tag_added: Tag added
             tag_renamed: 'Tag renamed'
+            too_much_tags: To avoid performance issues, you can't add more than %tags% tags at once or tags having more than %characters% characters.
     import:
         notice:
             failed: Import failed, please try again.