diff --git a/src/applications/files/config/PhabricatorFilesConfigOptions.php b/src/applications/files/config/PhabricatorFilesConfigOptions.php
--- a/src/applications/files/config/PhabricatorFilesConfigOptions.php
+++ b/src/applications/files/config/PhabricatorFilesConfigOptions.php
@@ -176,7 +176,11 @@
             'must be installed and the "%s" binary must be available to '.
             'the webserver for this to work.',
             'convert')),
-
+     $this->newOption('files.image-transform-size-limit', 'int', 4194304)
+        ->setDescription(
+          pht('Images larger than this size will not be rescaled'))
+        ->addExample(4194304, pht('Limit to 4MB'))
+        ->addExample(8388608, pht('Limit to 8MB')),
     );
   }
 
diff --git a/src/applications/files/transform/PhabricatorFileImageTransform.php b/src/applications/files/transform/PhabricatorFileImageTransform.php
--- a/src/applications/files/transform/PhabricatorFileImageTransform.php
+++ b/src/applications/files/transform/PhabricatorFileImageTransform.php
@@ -259,7 +259,8 @@
 
     $file = $this->file;
 
-    $max_size = (1024 * 1024 * 4);
+    $max_size = PhabricatorEnv::getEnvConfig(
+        'files.image-transform-size-limit');
     $img_size = $file->getByteSize();
     if ($img_size > $max_size) {
       throw new Exception(