diff --git a/app/assets/javascripts/discourse/lib/utilities.js b/app/assets/javascripts/discourse/lib/utilities.js
index 6d08ab93471..92c66cd53c2 100644
--- a/app/assets/javascripts/discourse/lib/utilities.js
+++ b/app/assets/javascripts/discourse/lib/utilities.js
@@ -179,7 +179,7 @@ Discourse.Utilities = {
 
     // check file size
     var fileSizeKB = file.size / 1024;
-    var maxSizeKB = Discourse.SiteSettings['max_' + type + '_size_kb'];
+    var maxSizeKB = 10 * 1024; // 10MB
     if (fileSizeKB > maxSizeKB) {
       bootbox.alert(I18n.t('post.errors.file_too_large', { max_size_kb: maxSizeKB }));
       return false;
@@ -243,7 +243,7 @@ Discourse.Utilities = {
 
         // entity too large, usually returned from the web server
         case 413:
-          var maxSizeKB = Discourse.SiteSettings.max_image_size_kb;
+          var maxSizeKB = 10 * 1024; // 10 MB
           bootbox.alert(I18n.t('post.errors.file_too_large', { max_size_kb: maxSizeKB }));
           return;
 
diff --git a/app/controllers/uploads_controller.rb b/app/controllers/uploads_controller.rb
index 9affe7d0f1d..57a1442ed66 100644
--- a/app/controllers/uploads_controller.rb
+++ b/app/controllers/uploads_controller.rb
@@ -52,7 +52,7 @@ def create_upload(type, file, url)
     begin
       # API can provide a URL
       if file.nil? && url.present? && is_api?
-        tempfile = FileHelper.download(url, SiteSetting.max_image_size_kb.kilobytes, "discourse-upload-#{type}") rescue nil
+        tempfile = FileHelper.download(url, 10.megabytes, "discourse-upload-#{type}") rescue nil
         filename = File.basename(URI.parse(url).path)
       else
         tempfile = file.tempfile
@@ -60,6 +60,15 @@ def create_upload(type, file, url)
         content_type = file.content_type
       end
 
+      # allow users to upload large images that will be automatically reduced to allowed size
+      if tempfile && tempfile.size > 0 && SiteSetting.max_image_size_kb > 0 && FileHelper.is_image?(filename)
+        attempt = 5
+        while attempt > 0 && tempfile.size > SiteSetting.max_image_size_kb.kilobytes
+          OptimizedImage.downsize(tempfile.path, tempfile.path, "80%", allow_animation: SiteSetting.allow_animated_thumbnails)
+          attempt -= 1
+        end
+      end
+
       upload = Upload.create_for(current_user.id, tempfile, filename, tempfile.size, content_type: content_type, image_type: type)
 
       if upload.errors.empty? && current_user.admin?
diff --git a/app/models/optimized_image.rb b/app/models/optimized_image.rb
index a70c86e63ad..a4bcc6112e4 100644
--- a/app/models/optimized_image.rb
+++ b/app/models/optimized_image.rb
@@ -139,25 +139,24 @@ def self.downsize_instructions_animated(from, to, dimensions, opts={})
   end
 
   def self.resize(from, to, width, height, opts={})
-    optimize("resize", from, to, width, height, opts)
+    optimize("resize", from, to, "#{width}x#{height}", opts)
   end
 
   def self.downsize(from, to, max_width, max_height, opts={})
-    optimize("downsize", from, to, max_width, max_height, opts)
+    optimize("downsize", from, to, "#{max_width}x#{max_height}", opts)
   end
 
-  def self.optimize(operation, from, to, width, height, opts={})
-    dim = dimensions(width, height)
+  def self.downsize(from, to, dimensions, opts={})
+    optimize("downsize", from, to, dimensions, opts)
+  end
+
+  def self.optimize(operation, from, to, dimensions, opts={})
     method_name = "#{operation}_instructions"
     method_name += "_animated" if !!opts[:allow_animation] && from =~ /\.GIF$/i
-    instructions = self.send(method_name.to_sym, from, to, dim, opts)
+    instructions = self.send(method_name.to_sym, from, to, dimensions, opts)
     convert_with(instructions, to)
   end
 
-  def self.dimensions(width, height)
-    "#{width}x#{height}"
-  end
-
   def self.convert_with(instructions, to)
     `#{instructions.join(" ")} &> /dev/null`
     return false if $?.exitstatus != 0