diff --git a/header.html b/header.html
index c34ab9b..63205cc 100644
--- a/header.html
+++ b/header.html
@@ -176,7 +176,7 @@
                 while (n[0] < a.length) {
                     let entry = a[n[0]];
                         mtime = new Date(entry.mtime),
-                        entry.mtime = `${mtime.toLocaleDateString()}  ${mtime.toLocaleTimeString()}`,
+                        entry.mtime = mtime.toISOString(),
                         url = `${pathname}${entry.name}`;
 
                     if (entry.type == 'directory') {