diff --git a/src/popup/views/addressDetail.js b/src/popup/views/addressDetail.js
index fd28e96..4f3ebec 100644
--- a/src/popup/views/addressDetail.js
+++ b/src/popup/views/addressDetail.js
@@ -95,18 +95,23 @@ function show() {
 function isoDate(timestamp) {
     const d = new Date(timestamp * 1000);
     const pad = (n) => String(n).padStart(2, "0");
+    const offsetMin = -d.getTimezoneOffset();
+    const sign = offsetMin >= 0 ? "+" : "-";
+    const absOff = Math.abs(offsetMin);
+    const tzStr = sign + pad(Math.floor(absOff / 60)) + ":" + pad(absOff % 60);
     return (
         d.getFullYear() +
         "-" +
         pad(d.getMonth() + 1) +
         "-" +
         pad(d.getDate()) +
-        " " +
+        "T" +
         pad(d.getHours()) +
         ":" +
         pad(d.getMinutes()) +
         ":" +
-        pad(d.getSeconds())
+        pad(d.getSeconds()) +
+        tzStr
     );
 }
 
diff --git a/src/popup/views/helpers.js b/src/popup/views/helpers.js
index 45329ea..f3d987d 100644
--- a/src/popup/views/helpers.js
+++ b/src/popup/views/helpers.js
@@ -226,18 +226,23 @@ function formatAddressHtml(address, ensName, maxLen, title) {
 function isoDate(timestamp) {
     const d = new Date(timestamp * 1000);
     const pad = (n) => String(n).padStart(2, "0");
+    const offsetMin = -d.getTimezoneOffset();
+    const sign = offsetMin >= 0 ? "+" : "-";
+    const absOff = Math.abs(offsetMin);
+    const tzStr = sign + pad(Math.floor(absOff / 60)) + ":" + pad(absOff % 60);
     return (
         d.getFullYear() +
         "-" +
         pad(d.getMonth() + 1) +
         "-" +
         pad(d.getDate()) +
-        " " +
+        "T" +
         pad(d.getHours()) +
         ":" +
         pad(d.getMinutes()) +
         ":" +
-        pad(d.getSeconds())
+        pad(d.getSeconds()) +
+        tzStr
     );
 }