diff --git a/youtube_dl/extractor/byutv.py b/youtube_dl/extractor/byutv.py
index ce25816f0..dda98059e 100644
--- a/youtube_dl/extractor/byutv.py
+++ b/youtube_dl/extractor/byutv.py
@@ -17,7 +17,7 @@ class BYUtvIE(InfoExtractor):
             'description': 'md5:e07269172baff037f8e8bf9956bc9747',
             'title': 'Season 5 Episode 5',
             'thumbnail': 're:^https?://.*\.jpg$',
-            'duration': 1486486,
+            'duration': 1486.486,
         },
         'params': {
             'skip_download': True,
diff --git a/youtube_dl/extractor/generic.py b/youtube_dl/extractor/generic.py
index b60684f98..e3bdff2d8 100644
--- a/youtube_dl/extractor/generic.py
+++ b/youtube_dl/extractor/generic.py
@@ -339,7 +339,7 @@ class GenericIE(InfoExtractor):
                 'id': 'BwY2RxaTrTkslxOfcan0UCf0YqyvWysJ',
                 'ext': 'mp4',
                 'title': '2cc213299525360.mov',  # that's what we get
-                'duration': 238231,
+                'duration': 238.231,
             },
             'add_ie': ['Ooyala'],
         },
@@ -351,7 +351,7 @@ class GenericIE(InfoExtractor):
                 'ext': 'mp4',
                 'title': '"Steve Jobs: Man in the Machine" trailer',
                 'description': 'The first trailer for the Alex Gibney documentary "Steve Jobs: Man in the Machine."',
-                'duration': 135427,
+                'duration': 135.427,
             },
             'params': {
                 'skip_download': True,
@@ -964,7 +964,7 @@ class GenericIE(InfoExtractor):
                 'ext': 'mp4',
                 'description': 'VIDEO: INDEX/MATCH versus VLOOKUP.',
                 'title': 'This is what separates the Excel masters from the wannabes',
-                'duration': 191933,
+                'duration': 191.933,
             },
             'params': {
                 # m3u8 downloads
diff --git a/youtube_dl/extractor/groupon.py b/youtube_dl/extractor/groupon.py
index 22ff7182f..63c05b6a6 100644
--- a/youtube_dl/extractor/groupon.py
+++ b/youtube_dl/extractor/groupon.py
@@ -19,7 +19,7 @@ class GrouponIE(InfoExtractor):
                 'ext': 'mp4',
                 'title': 'Bikram Yoga Huntington Beach | Orange County',
                 'description': 'md5:d41d8cd98f00b204e9800998ecf8427e',
-                'duration': 44961,
+                'duration': 44.961,
             },
         }],
         'params': {
diff --git a/youtube_dl/extractor/howcast.py b/youtube_dl/extractor/howcast.py
index 165b9f39e..e8f51e545 100644
--- a/youtube_dl/extractor/howcast.py
+++ b/youtube_dl/extractor/howcast.py
@@ -16,7 +16,7 @@ class HowcastIE(InfoExtractor):
             'description': 'md5:dbe792e5f6f1489027027bf2eba188a3',
             'timestamp': 1276081287,
             'upload_date': '20100609',
-            'duration': 56823,
+            'duration': 56.823,
         },
         'params': {
             # m3u8 download
diff --git a/youtube_dl/extractor/ooyala.py b/youtube_dl/extractor/ooyala.py
index 3b692e903..35067e271 100644
--- a/youtube_dl/extractor/ooyala.py
+++ b/youtube_dl/extractor/ooyala.py
@@ -24,7 +24,7 @@ class OoyalaBaseIE(InfoExtractor):
             'title': metadata['title'],
             'description': metadata.get('description'),
             'thumbnail': metadata.get('thumbnail_image') or metadata.get('promo_image'),
-            'duration': int_or_none(metadata.get('duration')),
+            'duration': float_or_none(metadata.get('duration'), 1000),
         }
 
         formats = []
@@ -78,7 +78,7 @@ class OoyalaIE(OoyalaBaseIE):
                 'ext': 'mp4',
                 'title': 'Explaining Data Recovery from Hard Drives and SSDs',
                 'description': 'How badly damaged does a drive have to be to defeat Russell and his crew? Apparently, smashed to bits.',
-                'duration': 853386,
+                'duration': 853.386,
             },
         }, {
             # Only available for ipad
@@ -87,7 +87,7 @@ class OoyalaIE(OoyalaBaseIE):
                 'id': 'x1b3lqZDq9y_7kMyC2Op5qo-p077tXD0',
                 'ext': 'mp4',
                 'title': 'Simulation Overview - Levels of Simulation',
-                'duration': 194948,
+                'duration': 194.948,
             },
         },
         {
@@ -99,7 +99,7 @@ class OoyalaIE(OoyalaBaseIE):
                 'id': 'FiOG81ZTrvckcchQxmalf4aQj590qTEx',
                 'ext': 'mp4',
                 'title': 'Divide Tool Path.mp4',
-                'duration': 204405,
+                'duration': 204.405,
             }
         }
     ]
diff --git a/youtube_dl/extractor/teachingchannel.py b/youtube_dl/extractor/teachingchannel.py
index 36a6fc679..e0477382c 100644
--- a/youtube_dl/extractor/teachingchannel.py
+++ b/youtube_dl/extractor/teachingchannel.py
@@ -16,7 +16,7 @@ class TeachingChannelIE(InfoExtractor):
             'ext': 'mp4',
             'title': 'A History of Teaming',
             'description': 'md5:2a9033db8da81f2edffa4c99888140b3',
-            'duration': 422255,
+            'duration': 422.255,
         },
         'params': {
             # m3u8 download
diff --git a/youtube_dl/extractor/vice.py b/youtube_dl/extractor/vice.py
index 7df87c31c..3db6286e4 100644
--- a/youtube_dl/extractor/vice.py
+++ b/youtube_dl/extractor/vice.py
@@ -15,7 +15,7 @@ class ViceIE(InfoExtractor):
                 'id': '43cW1mYzpia9IlestBjVpd23Yu3afAfp',
                 'ext': 'mp4',
                 'title': 'VICE_COWBOYCAPITALISTS_PART01_v1_VICE_WM_1080p.mov',
-                'duration': 725983,
+                'duration': 725.983,
             },
             'params': {
                 # Requires ffmpeg (m3u8 manifest)