diff --git a/public/locales/ja/common.json b/public/locales/ja/common.json
index a1cb4be3..a651ef4b 100644
--- a/public/locales/ja/common.json
+++ b/public/locales/ja/common.json
@@ -10,7 +10,8 @@
         "bibitrate": "{{value, rate(bits: true; binary: true)}}",
         "percent": "{{value, percent}}",
         "number": "{{value, number}}",
-        "ms": "{{value, number}}"
+        "ms": "{{value, number}}",
+        "date": "{{value, date}}"
     },
     "widget": {
         "missing_type": "見つからないウィジェットタイプ: {{type}}",