diff --git a/app/models/concerns/tipline_content_multimedia.rb b/app/models/concerns/tipline_content_multimedia.rb
index 6a7c9f18a6..210ef27ea3 100644
--- a/app/models/concerns/tipline_content_multimedia.rb
+++ b/app/models/concerns/tipline_content_multimedia.rb
@@ -3,6 +3,7 @@
 # Attached file: image, audio or video
 
 module TiplineContentMultimedia
+  class ConvertedFileTooLarge < StandardError; end
   extend ActiveSupport::Concern
 
   included do
@@ -50,11 +51,12 @@ def convert_header_file_audio_or_video(type)
       output_path = File.join(Rails.root, 'tmp', "#{content_name}-#{type}-output-#{self.id}-#{now}.mp4")
       video = FFMPEG::Movie.new(input.path)
       video.transcode(output_path, options)
+      raise TiplineContentMultimedia::ConvertedFileTooLarge.new('Converted file for tipline content is too large') if (File.size(output_path).to_f / 1024000.0) > self.header_file_video_max_size
       path = "#{content_name}/video/#{content_name}-#{type}-#{self.id}-#{now}"
       CheckS3.write(path, 'video/mp4', File.read(output_path))
       url = CheckS3.public_url(path)
     rescue StandardError => e
-      CheckSentry.notify(e)
+      CheckSentry.notify(e, class: self.class, id: self.id)
     ensure
       FileUtils.rm_f input.path
       FileUtils.rm_f output_path
diff --git a/app/models/concerns/tipline_content_video.rb b/app/models/concerns/tipline_content_video.rb
index 161d1c71ab..668247151c 100644
--- a/app/models/concerns/tipline_content_video.rb
+++ b/app/models/concerns/tipline_content_video.rb
@@ -4,8 +4,12 @@ module TiplineContentVideo
   extend ActiveSupport::Concern
 
   # MP4 less than 10 MB (WhatsApp supports 16 MB, let's be safe)
+  def header_file_video_max_size
+    10
+  end
+
   def validate_header_file_video
-    self.validate_header_file(10, ['mp4'], 'errors.messages.video_too_large')
+    self.validate_header_file(self.header_file_video_max_size, ['mp4'], 'errors.messages.video_too_large')
   end
 
   def should_convert_header_video?
diff --git a/test/data/h265-video.mp4 b/test/data/h265-video.mp4
new file mode 100644
index 0000000000..c799f564a1
Binary files /dev/null and b/test/data/h265-video.mp4 differ
diff --git a/test/models/tipline_newsletter_test.rb b/test/models/tipline_newsletter_test.rb
index b857e51275..4f9dfcd9cb 100644
--- a/test/models/tipline_newsletter_test.rb
+++ b/test/models/tipline_newsletter_test.rb
@@ -479,4 +479,15 @@ def teardown
       create_tipline_newsletter send_every: nil
     end
   end
+
+  test 'should validate video size after converting' do
+    # This test file is 300 KB, but 1.6 MB after converting
+    WebMock.stub_request(:get, /:9000/).to_return(body: File.read(File.join(Rails.root, 'test', 'data', 'h265-video.mp4')))
+    TiplineNewsletter.any_instance.stubs(:new_file_uploaded?).returns(true)
+    TiplineNewsletter.any_instance.stubs(:header_file_video_max_size).returns(1) # Maximum 1 MB
+    CheckSentry.stubs(:notify).once
+    Sidekiq::Testing.inline! do
+      create_tipline_newsletter header_type: 'video', header_file: 'h265-video.mp4'
+    end
+  end
 end