diff --git a/app/models/display_ad.rb b/app/models/display_ad.rb
index b29d9b636..5b1463efe 100644
--- a/app/models/display_ad.rb
+++ b/app/models/display_ad.rb
@@ -7,6 +7,9 @@ class DisplayAd < ApplicationRecord
                                             "Sidebar Right",
                                             "Below the comment section"].freeze
 
+  POST_WIDTH = 775
+  SIDEBAR_WIDTH = 350
+
   belongs_to :organization, optional: true
   has_many :display_ad_events, dependent: :destroy
 
@@ -41,6 +44,11 @@ class DisplayAd < ApplicationRecord
                                                             tags: MarkdownProcessor::AllowedTags::DISPLAY_AD,
                                                             attributes: MarkdownProcessor::AllowedAttributes::DISPLAY_AD
     html = stripped_html.delete("\n")
-    self.processed_html = Html::Parser.new(html).prefix_all_images(350, synchronous_detail_detection: true).html
+    self.processed_html = Html::Parser.new(html)
+      .prefix_all_images(prefix_width, synchronous_detail_detection: true).html
+  end
+
+  def prefix_width
+    placement_area.to_s == "post_comments" ? POST_WIDTH : SIDEBAR_WIDTH
   end
 end