diff --git a/README.md b/README.md
index 61ab388c36..2ab8d2de9f 100644
--- a/README.md
+++ b/README.md
@@ -741,6 +741,7 @@ The basic usage is not to set any template arguments when downloading a single f
  - `channel_id` (string): Id of the channel
  - `location` (string): Physical location where the video was filmed
  - `duration` (numeric): Length of the video in seconds
+ - `duration_string` (string): Length of the video (HH-mm-ss)
  - `view_count` (numeric): How many users have watched the video on the platform
  - `like_count` (numeric): Number of positive ratings of the video
  - `dislike_count` (numeric): Number of negative ratings of the video
diff --git a/youtube_dlc/YoutubeDL.py b/youtube_dlc/YoutubeDL.py
index e632ba708f..19666d0ad1 100644
--- a/youtube_dlc/YoutubeDL.py
+++ b/youtube_dlc/YoutubeDL.py
@@ -908,6 +908,10 @@ class YoutubeDL(object):
         self.add_extra_info(ie_result, {
             'extractor': ie.IE_NAME,
             'webpage_url': url,
+            'duration_string': (
+                formatSeconds(ie_result['duration'], '-')
+                if ie_result.get('duration', None) is not None
+                else None),
             'webpage_url_basename': url_basename(url),
             'extractor_key': ie.ie_key(),
         })
diff --git a/youtube_dlc/utils.py b/youtube_dlc/utils.py
index 6ed8629a7a..21e3481a0f 100644
--- a/youtube_dlc/utils.py
+++ b/youtube_dlc/utils.py
@@ -2285,11 +2285,11 @@ def decodeOption(optval):
     return optval
 
 
-def formatSeconds(secs):
+def formatSeconds(secs, delim=':'):
     if secs > 3600:
-        return '%d:%02d:%02d' % (secs // 3600, (secs % 3600) // 60, secs % 60)
+        return '%d%s%02d%s%02d' % (secs // 3600, delim, (secs % 3600) // 60, delim, secs % 60)
     elif secs > 60:
-        return '%d:%02d' % (secs // 60, secs % 60)
+        return '%d%s%02d' % (secs // 60, delim, secs % 60)
     else:
         return '%d' % secs