diff --git a/vite.config.ts b/vite.config.ts
index 4a1c901..7986fec 100644
--- a/vite.config.ts
+++ b/vite.config.ts
@@ -33,6 +33,7 @@ const SUPPORTED_LANGUAGES = [
   'zh',
   'zh-TW',
   'ko',
+  'ja',
 ] as const;
 const LANG_REGEX = new RegExp(
   `^/(${SUPPORTED_LANGUAGES.join('|')})(?:/(.*))?$`