diff --git a/app/assets/javascripts/app/controllers/_application_controller.js.coffee b/app/assets/javascripts/app/controllers/_application_controller.js.coffee
index 03c859fb2..5d5014acd 100644
--- a/app/assets/javascripts/app/controllers/_application_controller.js.coffee
+++ b/app/assets/javascripts/app/controllers/_application_controller.js.coffee
@@ -160,13 +160,7 @@ class App.Controller extends Spine.Controller
 
   # human readable file size
   humanFileSize: (size) =>
-    if size > ( 1024 * 1024 )
-      size = Math.round( size / ( 1024 * 1024 ) ) + ' MB'
-    else if size > 1024
-      size = Math.round( size / 1024 ) + ' KB'
-    else
-      size = size + ' Bytes'
-    size
+    App.Utils.humanFileSize(size)
 
   # human readable time
   humanTime: ( time, escalation, long = true ) =>
diff --git a/app/assets/javascripts/app/index.js.coffee b/app/assets/javascripts/app/index.js.coffee
index 5cb31e6a4..ae5bd2aa7 100644
--- a/app/assets/javascripts/app/index.js.coffee
+++ b/app/assets/javascripts/app/index.js.coffee
@@ -212,6 +212,10 @@ class App extends Spine.Controller
 
         result
 
+      # define file size helper
+      params.humanFileSize = ( size ) ->
+        App.Utils.humanFileSize(size)
+
       # define template
       JST["app/views/#{name}"](params)
     template
diff --git a/app/assets/javascripts/app/lib/app_post/utils.js.coffee b/app/assets/javascripts/app/lib/app_post/utils.js.coffee
index 40ee90984..876d2bb51 100644
--- a/app/assets/javascripts/app/lib/app_post/utils.js.coffee
+++ b/app/assets/javascripts/app/lib/app_post/utils.js.coffee
@@ -273,3 +273,13 @@ class App.Utils
     attachmentTranslatedRegExp = new RegExp( attachmentTranslated, 'i' )
     return true if message.match( attachmentTranslatedRegExp )
     false
+
+  # human readable file size
+  @humanFileSize: (size) =>
+    if size > ( 1024 * 1024 )
+      size = Math.round( size / ( 1024 * 1024 ) ) + ' MB'
+    else if size > 1024
+      size = Math.round( size / 1024 ) + ' KB'
+    else
+      size = size + ' Bytes'
+    size
diff --git a/app/assets/javascripts/app/views/ticket_zoom/article_view.jst.eco b/app/assets/javascripts/app/views/ticket_zoom/article_view.jst.eco
index 25007c319..9ce99c92b 100644
--- a/app/assets/javascripts/app/views/ticket_zoom/article_view.jst.eco
+++ b/app/assets/javascripts/app/views/ticket_zoom/article_view.jst.eco
@@ -56,7 +56,7 @@
               <% for attachment in @article.attachments: %>
                 <div class="attachment horizontal">
                   <a class="attachment-name u-highlight" href="<%= App.Config.get('api_path') %>/ticket_attachment/<%= @article.ticket_id %>/<%= @article.id %>/<%= attachment.id %>" target="_blank" data-type="attachment"><%= attachment.filename %></a>
-                  <div class="attachment-size"><%= attachment.size %></div>
+                  <div class="attachment-size"><%- @humanFileSize(attachment.size) %></div>
                 </div>
               <% end %>
             </div>