Three of the top social networks have undergone a redesign in the last year. This social media cheat sheet details the image sizes you’ll need for your Facebook, Twitter, and YouTube accounts.

In February 2012, Facebook updated the look of its Timeline for Pages to include cover photos and featured posts, among other changes.

Twitter’s December 2011 redesign, “Let’s Fly,” included new backgrounds for profiles.

YouTube has changed quite a bit in the last year. The latest channel redesign, which will bring branded banners to all users, was announced a couple weeks ago. But it’s only available to select partners right now and is not reflected in this chart. Check YouTube’s channel art guidelines for updates.

Is your page or profile up to date? See the cheat sheet below, courtesy of Cerebra.