You might have come across a warning while watching videos on Youtube asking you to sign- in to watch 18+ adult videos which contain either explicit language or violence.

1. Copy the video URL (present in the address bar of the browser)
2. Here the URL is http://www.youtube.com/watch?v=O07u7KdRVo0
3. Now just replace the word watch with watch_popup and now the URL ishttp://www.youtube.com/watch_popup?v=O07u7KdRVo0
4. That’s it. You are done.

1. Copy the video URL (present in the address bar of the browser)
2. Here the URL is http://www.youtube.com/watch?v=O07u7KdRVo0
3. Here O07u7KdRVo0 is the video_id.
4. Now, use this video_id as the following URL http://www.youtube.com/v/video_id?fs=1
5. Now replace the video_id with the O07u7KdRVo0 to get

http://www.youtube.com/v/O07u7KdRVo0?fs=1

1. This method is for some URLs which have different format like below:
   http://www.youtube.com/verify_age?next_url=/watch%3Fv%3DJaFVr_cJJIY
   
   
2. Such URL is same as the following URL except that the symbols are coded
   http://www.youtube.com/verify_age?next_url=/watch?v=JaFVr_cJJIY
   Just keep track of the last 11 letters –as said before.
3. So, finally to view such videos it is same as the method 2 – change the above URL to the following
   http://www.youtube.com/v/JaFVr_cJJIY?fs=1