diff --git a/how-to/upload-encrypted-data/file.md b/how-to/upload-encrypted-data/file.md
index 5a168b4..2bd7af0 100644
--- a/how-to/upload-encrypted-data/file.md
+++ b/how-to/upload-encrypted-data/file.md
@@ -80,6 +80,13 @@ function App() {
   // Define your API Key (should be replaced with secure environment variables in production)
   const apiKey = process.env.REACT_APP_API_KEY
 
+//progressCallback in percentage
+  const progressCallback = (progressData) => {
+    let percentageDone =
+      100 - (progressData?.total / progressData?.uploaded)?.toFixed(2)
+    console.log(percentageDone)
+  }
+
   // Function to sign the authentication message using Wallet
   const signAuthMessage = async () => {
     if (window.ethereum) {