diff --git a/gallery_dl/iso639_1.py b/gallery_dl/iso639_1.py
new file mode 100644
index 00000000..2e639e9f
--- /dev/null
+++ b/gallery_dl/iso639_1.py
@@ -0,0 +1,41 @@
+# -*- coding: utf-8 -*-
+
+# Copyright 2015 Mike Fährmann
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 as
+# published by the Free Software Foundation.
+
+"""Conversion between language names and ISO 639-1 codes"""
+
+def code_to_language(code, default="English"):
+    """Map an ISO 639-1 language code to its actual name"""
+    return codes.get(code, default)
+
+def language_to_code(lang, default="en"):
+    """Map a language name to its ISO 639-1 code"""
+    for code, language in codes.items():
+        if language == lang:
+            return code
+    return default
+
+codes = {
+    "cs": "Czech",
+    "da": "Danish",
+    "de": "German",
+    "en": "English",
+    "es": "Spanish",
+    "fi": "Finnish",
+    "fr": "French",
+    "it": "Italian",
+    "jp": "Japanese",
+    "ko": "Korean",
+    "nl": "Dutch",
+    "no": "Norwegian",
+    "pl": "Polish",
+    "pt": "Portuguese",
+    "ru": "Russian",
+    "sv": "Swedish",
+    "vi": "Vietnamese",
+    "zh": "Chinese",
+}
diff --git a/test/test_iso639_1.py b/test/test_iso639_1.py
new file mode 100644
index 00000000..1e705ce0
--- /dev/null
+++ b/test/test_iso639_1.py
@@ -0,0 +1,25 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+# Copyright 2015 Mike Fährmann
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 as
+# published by the Free Software Foundation.
+
+import unittest
+import gallery_dl.iso639_1 as iso639_1
+
+class TestISO639_1(unittest.TestCase):
+
+    def test_code_to_language(self):
+        self.assertEqual(iso639_1.code_to_language("en"), "English")
+        self.assertEqual(iso639_1.code_to_language("xx"), "English")
+        self.assertEqual(iso639_1.code_to_language("xx", default=None), None)
+    def test_language_to_code(self):
+        self.assertEqual(iso639_1.language_to_code("English"), "en")
+        self.assertEqual(iso639_1.language_to_code("Nothing"), "en")
+        self.assertEqual(iso639_1.language_to_code("Nothing", default=None), None)
+
+if __name__ == '__main__':
+    unittest.main()