http://img.youtube.com/vi/<insert-youtube-video-id-here>/0.jpgThe first one in the list is a full size image and others are thumbnail images. The default thumbnail image (ie. one of
http://img.youtube.com/vi/<insert-youtube-video-id-here>/1.jpg
http://img.youtube.com/vi/<insert-youtube-video-id-here>/2.jpg
http://img.youtube.com/vi/<insert-youtube-video-id-here>/3.jpg
1.jpg
, 2.jpg
, 3.jpg
) is:
http://img.youtube.com/vi/<insert-youtube-video-id-here>/default.jpgFor the high quality version of the thumbnail use a url similar to this:
http://img.youtube.com/vi/<insert-youtube-video-id-here>/hqdefault.jpgThere is also a medium quality version of the thumbnail, using a url similar to the HQ:
http://img.youtube.com/vi/<insert-youtube-video-id-here>/mqdefault.jpgFor the standard definition version of the thumbnail, use a url similar to this:
http://img.youtube.com/vi/<insert-youtube-video-id-here>/sddefault.jpgFor the maximum resolution version of the thumbnail use a url similar to this:
http://img.youtube.com/vi/<insert-youtube-video-id-here>/maxresdefault.jpgAll of the above urls are available over https too. Just change http to
https
in any of the above urls. Additionally, the slightly shorter hostname i3.ytimg.com
works in place of img.youtube.com in the example urls above.Alternatively, you can use the YouTube Data API (v3) or the older YouTube API v2.0 to get thumbnail images.