diff --git a/bin/audit_iaids.rb b/bin/audit_iaids.rb
new file mode 100755
index 0000000..f1be5a6
--- /dev/null
+++ b/bin/audit_iaids.rb
@@ -0,0 +1,98 @@
+#!/usr/bin/env ruby
+
+require 'dotenv'
+require 'fileutils'
+require 'json'
+require 'pathname'
+require 'ruby-progressbar'
+
+Dotenv.load('.env.production')
+load 'lib/space_stone.rb'
+
+def fetch_filenames_from_ia(iaid, data)
+  ia_download_service = SpaceStone::IaDownload.new(id: iaid)
+  url = "#{ia_download_service.remote_file_link}/" # trailing slash matters
+
+  response = begin
+               HTTParty.get(url, headers: { 'Cookie' => ia_download_service.login_cookies })
+             rescue Errno::ECONNREFUSED
+               data['status'] = "ERROR -- Couldn't connect to IA"
+               false
+             end
+  return [] if response == false || response.body.nil? || response.body.empty?
+
+  page = Nokogiri::HTML(response.body)
+  nodeset = page.css('a[href]')
+  hrefs = nodeset.map { |element| element['href'] }
+  # %2F is a URL-encoded slash ("/")
+  hrefs.grep(/download.*\.jp2$/).map { |file_path| file_path.split('%2F').last }
+end
+
+def fetch_filenames_from_s3(prefix)
+  @bucket
+    .objects(prefix:)
+    .entries
+    .map { |path| path.key.split('/').last }
+    .sort
+end
+
+def basenames(paths)
+  paths.map { |p| p.split('.')[0] }
+end
+
+def log_status(data)
+  return if data['status'] == "ERROR -- Couldn't connect to IA"
+
+  data['status'] = if data['ia_files'].nil? || data['ia_files'].empty?
+                     'ERROR -- No files found in IA'
+                   elsif !data['missing_files'].empty? || !data['missing_ocr'].empty? || !data['missing_thumbnails'].empty?
+                     'WARN'
+                   else
+                     'OK'
+                   end
+end
+
+# ---
+
+json_path = Pathname.new(ARGV[0])
+raise "No file found at #{json_path}" unless json_path.exist?
+
+hash = JSON.parse(File.read(json_path))
+@bucket = SpaceStone::S3Service.bucket
+puts "\nTrack progress by tailing tmp/audit_debug.log\n\n"
+progressbar = ProgressBar.create(total: hash.keys.size, format: '%a %e %P% Processed: %c from %C')
+
+begin
+  hash.each do |iaid, data|
+    data['last_checked'] = DateTime.now.strftime('%Y-%m-%dT%H:%M:%S')
+
+    if !data.key?('ia_files') || data['ia_files'].empty?
+      data['ia_files'] = fetch_filenames_from_ia(iaid, data)
+    end
+
+    data['s3_files'] = fetch_filenames_from_s3("#{iaid}/downloads")
+    data['s3_ocr'] = fetch_filenames_from_s3("#{iaid}/ocr")
+    data['s3_thumbnails'] = fetch_filenames_from_s3("#{iaid}/thumbnails")
+
+    data['missing_files'] = basenames(data['ia_files']) - basenames(data['s3_files'])
+    data['missing_ocr'] = basenames(data['ia_files']) - basenames(data['s3_ocr'])
+    data['missing_thumbnails'] = basenames(data['ia_files']) - basenames(data['s3_thumbnails'])
+
+    log_status(data)
+    progressbar.increment
+    File.open('tmp/audit_debug.log', 'a') do |f|
+      f.puts "#{iaid} -- #{data['status']}"
+    end
+    # progressbar.increment
+  end
+ensure
+  puts "\nBacking up existing data to #{json_path}.bak"
+  FileUtils.cp(json_path, "#{json_path}.bak")
+
+  File.open(json_path, 'w') do |file|
+    # file.puts JSON.pretty_generate(JSON.parse(hash.to_json))
+    file.puts hash.to_json
+  end
+
+  puts "\nOutput: #{json_path}"
+end