diff --git a/youtube_dl/downloader/common.py b/youtube_dl/downloader/common.py
index 8482cbd84..c23263511 100644
--- a/youtube_dl/downloader/common.py
+++ b/youtube_dl/downloader/common.py
@@ -242,12 +242,14 @@ class FileDownloader(object):
             if self.params.get('noprogress', False):
                 self.to_screen('[download] Download completed')
             else:
-                s['_total_bytes_str'] = format_bytes(s['total_bytes'])
+                if s.get('total_bytes') is not None:
+                    s['_total_bytes_str'] = format_bytes(s['total_bytes'])
+                    msg_template = '100%% of %(_total_bytes_str)s'
+                else:
+                    msg_template = 'Completed'
                 if s.get('elapsed') is not None:
                     s['_elapsed_str'] = self.format_seconds(s['elapsed'])
-                    msg_template = '100%% of %(_total_bytes_str)s in %(_elapsed_str)s'
-                else:
-                    msg_template = '100%% of %(_total_bytes_str)s'
+                    msg_template += ' in %(_elapsed_str)s'
                 self._report_progress_status(
                     msg_template % s, is_last_line=True)