diff --git a/tools/translation_analysis.php b/tools/translation_analysis.php
new file mode 100644
index 000000000..f4cfd1f3a
--- /dev/null
+++ b/tools/translation_analysis.php
@@ -0,0 +1,134 @@
+<?php
+// +-----------------------------------------------------------------------+
+// | Piwigo - a PHP based picture gallery                                  |
+// +-----------------------------------------------------------------------+
+// | Copyright(C) 2008-2009 Piwigo Team                  http://piwigo.org |
+// | Copyright(C) 2003-2008 PhpWebGallery Team    http://phpwebgallery.net |
+// | Copyright(C) 2002-2003 Pierrick LE GALL   http://le-gall.net/pierrick |
+// +-----------------------------------------------------------------------+
+// | This program is free software; you can redistribute it and/or modify  |
+// | it under the terms of the GNU General Public License as published by  |
+// | the Free Software Foundation                                          |
+// |                                                                       |
+// | This program is distributed in the hope that it will be useful, but   |
+// | WITHOUT ANY WARRANTY; without even the implied warranty of            |
+// | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      |
+// | General Public License for more details.                              |
+// |                                                                       |
+// | You should have received a copy of the GNU General Public License     |
+// | along with this program; if not, write to the Free Software           |
+// | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, |
+// | USA.                                                                  |
+// +-----------------------------------------------------------------------+
+
+define('PHPWG_ROOT_PATH', '../');
+include_once( PHPWG_ROOT_PATH.'include/common.inc.php' );
+include_once( PHPWG_ROOT_PATH.'tools/translation_validated.inc.php' );
+$languages = array_keys(get_languages());
+
+$page['ref_compare'] = 'en_UK';
+$page['ref_default_values'] = 'en_UK';
+
+$file_list = array('common', 'admin', 'install', 'upgrade');
+
+$metalang = array();
+
+// preload reference languages
+$metalang[ $page['ref_compare'] ] = load_metalang($page['ref_compare'], $file_list);
+$metalang[ $page['ref_default_values'] ] = load_metalang($page['ref_default_values'], $file_list);
+
+foreach ($languages as $language)
+{
+  if (in_array($language, array($page['ref_compare'], $page['ref_default_values'])))
+  {
+    continue;
+  }
+  echo '<h2>'.$language.'</h2>';
+  $metalang[$language] = load_metalang($language, $file_list);
+
+  foreach ($file_list as $file)
+  {
+    if (isset($metalang[ $language ][$file]))
+    {
+      $missing_keys = array_diff(
+        array_keys($metalang[ $page['ref_compare'] ][$file]),
+        array_keys($metalang[ $language ][$file])
+        );
+
+      $output_missing = '';
+      foreach ($missing_keys as $key)
+      {
+        $output_missing.= get_line_to_translate($file, $key);
+      }
+
+      // strings not "really" translated?
+      $output_duplicated = '';
+      foreach (array_keys($metalang[$language][$file]) as $key)
+      {
+        $exceptions = array('Level 0');
+        if (in_array($key, $exceptions))
+        {
+          continue;
+        }
+
+        if (isset($validated_keys[$language]) and in_array($key, $validated_keys[$language]))
+        {
+          continue;
+        }
+        
+        $local_value = $metalang[$language][$file][$key];
+        $ref_value = $metalang[ $page['ref_default_values'] ][$file][$key];
+        if ($local_value == $ref_value)
+        {
+          $output_duplicated.= get_line_to_translate($file, $key);
+        }
+      }
+
+      if ('' != $output_missing or '' != $output_duplicated)
+      {
+        $output = '';
+        if ('' != $output_missing)
+        {
+          $output.= "// missing translations\n".$output_missing;
+        }
+        if ('' != $output_duplicated)
+        {
+          $output.= "\n// untranslated yet\n".$output_duplicated;
+        }
+        echo '<h3>'.$file.'.lang.php</h3>';
+        echo '<textarea style="width:100%;height:150px;">'.$output.'</textarea>';
+      }
+    }
+    else
+    {
+      echo '<h3>'.$file.'.lang.php is missing</h3>';
+    }
+  }
+}
+
+function load_metalang($language, $file_list)
+{
+  global $lang, $user;
+  
+  $metalang = array();
+  foreach ($file_list as $file)
+  {
+    $lang = array();
+    $user['language'] = $language;
+    if (load_language($file.'.lang', '', array('language'=>$language, 'no_fallback'=>true)))
+    {
+      $metalang[$file] = $lang;
+    }
+  }
+  return $metalang;
+}
+
+function get_line_to_translate($file, $key)
+{
+  global $metalang, $page;
+  
+  $print_key = str_replace("'", '\\\'', $key);
+  $print_value = str_replace("'", '\\\'', $metalang[ $page['ref_default_values'] ][$file][$key]);
+  return '$'."lang['".$print_key."'] = '".$print_value."';\n";
+}
+?>
\ No newline at end of file
diff --git a/tools/translation_validated.inc.php b/tools/translation_validated.inc.php
new file mode 100644
index 000000000..902d6d384
--- /dev/null
+++ b/tools/translation_validated.inc.php
@@ -0,0 +1,121 @@
+<?php
+$validated_keys = array(
+  'fr_FR' => array(
+    'Dimensions',
+    'Identification',
+    'Notification',
+    'Tag',
+    'Tags',
+    'admin',
+    'identification',
+    'redirect_msg',
+    'search_date_from',
+    'title_menu',
+    'IP: %s',
+    'Email: %s',
+    '%d element',
+    '%d elements',
+    '%d association',
+    '%d associations',
+    '%d tag',
+    '%d tags',
+    'Actions',
+    'Description',
+    'Informations',
+    'Maintenance',
+    'Options',
+    'Plugins',
+    'Position',
+    'Validation',
+    'Version',
+    'config',
+    'Date',
+    'instructions',
+    'is_high_disabled',
+    'nbm_content_goto_2',
+    'nbm_content_hello_2',
+    'nbm_item_notification',
+    'nbm_send_options',
+    'permissions',
+    'public',
+    'site_local',
+    'update_simulation_title',
+    'IP',
+    'image',
+    'section',
+    'tags',
+    'high',
+    'c13y_Correction',
+    'Level 1',
+    'Level 8',
+    'FORUM',
+    'EXTENSIONS',
+    'WIKI / DOC',
+    'Installation',
+    'step1_host_info',
+    ),
+  'es_ES' => array(
+    'Tag',
+    'Tags',
+	'IP: %s',
+	'Email: %s',
+	'No',
+	'%d tag',
+	'%d tags',
+	'Plugins',
+	'is_high_disabled',
+	'nbm_content_goto_2',
+	'nbm_content_hello_2',
+	'site_local',
+	'update_simulation_title',
+	'IP',
+	'Level 8',
+	'DEMO',
+	'BUGS',
+	'step1_host_info',
+    ),
+  'da_DK' => array(
+ 	'Installation',
+	'install_webmaster',
+	'step1_host',
+	'step1_host_info',
+	'step1_pass',
+	'step2_pwd',
+	'%d Kb',
+	'%d hit',
+	'%d hits',
+	'Connection settings',
+	'Connection',
+	'Display',
+	'Filter',
+	'Links',
+	'N/A',
+	'Password',
+	'Quick connect',
+	'RSS feed',
+	'Reset',
+	'Tag',
+	'Tags',
+	'Webmaster',
+	'author(s) : %s',
+	'admin',
+	'caddie',
+	'download',
+	'logout',
+	'powered_by',
+	'remember_me',
+	'slideshow',
+	'sql_queries_in',
+	'thumbnails',
+	'title_menu',
+	'upload_author',
+	'IP: %s',
+	'Browser: %s',
+	'Author: %s',
+	'Email: %s',
+	'Admin: %s',
+	'Rank',
+	'cloud',
+	),
+  );
+?>
\ No newline at end of file