diff --git a/app/models/media_attachment.rb b/app/models/media_attachment.rb
index ea17bae1d..4dcf54520 100644
--- a/app/models/media_attachment.rb
+++ b/app/models/media_attachment.rb
@@ -121,7 +121,7 @@ class MediaAttachment < ApplicationRecord
   include Attachmentable
 
   validates :account, presence: true
-  validates :description, length: { maximum: 420 }, if: :local?
+  validates :description, length: { maximum: 666 }, if: :local?
 
   scope :attached,   -> { where.not(status_id: nil).or(where.not(scheduled_status_id: nil)) }
   scope :unattached, -> { where(status_id: nil, scheduled_status_id: nil) }