diff --git a/data/locales.json b/data/locales.json
index ada43a485..1e2326e07 100644
--- a/data/locales.json
+++ b/data/locales.json
@@ -3,8 +3,8 @@
     "bs",
     "ca",
     "zh",
-    "zh_TW",
     "hr",
+    "zh-TW",
     "cs",
     "da",
     "nl",
diff --git a/data/update_locales.js b/data/update_locales.js
index 3d3d3cf91..da89a13c6 100644
--- a/data/update_locales.js
+++ b/data/update_locales.js
@@ -75,7 +75,7 @@ function getLanguages(resource, callback) {
         function(err, resp, body) {
         if (err) return callback(err);
         callback(null, JSON.parse(body).available_languages.map(function(d) {
-            return d.code;
+            return d.code.replace(/_/g, '-');
         }).filter(function(d) {
             return d !== 'en';
         }));
diff --git a/dist/locales/zh_TW.json b/dist/locales/zh-TW.json
similarity index 100%
rename from dist/locales/zh_TW.json
rename to dist/locales/zh-TW.json