diff --git a/src/js/backend.js b/src/js/backend.js
index d88726e..2918805 100644
--- a/src/js/backend.js
+++ b/src/js/backend.js
@@ -19,11 +19,11 @@ document.addEventListener('DOMContentLoaded', function () {
 });
 
 // Function to convert seconds to human readable duration
-function formatDuration(seconds) {
+function formatDuration(seconds, isMilliseconds = false) {
   if (!seconds || isNaN(seconds)) return seconds;
 
   // Convert to number in case it's a string
-  const totalSeconds = parseFloat(seconds);
+  const totalSeconds = isMilliseconds ? parseFloat(seconds) / 1000 : parseFloat(seconds);
 
   // Calculate days, hours, minutes, seconds
   const days = Math.floor(totalSeconds / 86400);
@@ -163,7 +163,9 @@ function processTimestamps(
       typeof value === 'number' &&
       document.getElementById('replaceKeysOption').checked
     ) {
-      result[key] = formatDuration(value);
+      // Check if the key is 'duration' to know if it's in milliseconds
+      const isMilliseconds = key === 'duration';
+      result[key] = formatDuration(value, isMilliseconds);
     } else if (typeof value === 'object' && value !== null) {
       result[key] = processTimestamps(
         value,