diff --git a/app/views/posts/template_field/_url.haml b/app/views/posts/template_field/_url.haml
index 4cf0270..23e4ac4 100644
--- a/app/views/posts/template_field/_url.haml
+++ b/app/views/posts/template_field/_url.haml
@@ -2,3 +2,4 @@
   value,
   class: 'form-control',
   required: template.required?
+%small.text-muted.form-text= t('posts.url')
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 128bc58..fdc0e7b 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -221,3 +221,4 @@ en:
       max: 'The maximum value is %{max}'
     image:
       multiple: 'You can select several images'
+    url: 'The address must start with http:// or https://'
diff --git a/config/locales/es.yml b/config/locales/es.yml
index d6b1af1..46a5943 100644
--- a/config/locales/es.yml
+++ b/config/locales/es.yml
@@ -217,3 +217,4 @@ es:
       max: 'El valor máximo es %{max}'
     image:
       multiple: 'Puedes seleccionar varias imágenes'
+    url: 'La dirección debe comenzar con http:// o https://'