diff --git a/index.js b/index.js
index f64fa00..27df061 100644
--- a/index.js
+++ b/index.js
@@ -217,6 +217,7 @@ S3Storage.prototype._handleFile = function (req, file, cb) {
 
     upload.on('httpUploadProgress', function (ev) {
       if (ev.total) currentSize = ev.total
+      else if (ev.loaded) currentSize = ev.loaded
     })
 
     util.callbackify(upload.done.bind(upload))(function (err, result) {