YouTube is down and it seems to be a worldwide issue. YouTubers and Vloggers can now take a quick rest while YouTube tries to solve this big headache.
Here is from YouTube Twitter account.
Thanks for your reports about YouTube, YouTube TV and YouTube Music access issues. We’re working on resolving this and will let you know once fixed. We apologize for any inconvenience this may cause and will keep you updated.
— Team YouTube (@TeamYouTube) October 17, 2018