Thanks for reaching out. Here's the Help Center article which helps you with resolutions and ratios: https://goo.gl/CCdvJ6 . Hope this helps.
@TeamYouTube @YouTube @YTCreators what are all the ratios/frame sizes youtube takes?
-
-
-
Thank you
End of conversation
New conversation -
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.