Social Media Dimensions Blueprint

http://socialmediatoday.com/tara-urso/2393561/social-media-dimensions-blueprint?utm_source=smt_newsletter&utm_medium=email&utm_campaign=newsletter&inf_contact_key=2aa60dafd36406f25bfb5459b5c8a22217ccb31d307d3a793341933b78c5c9c6

While Twitter suggests that you upload an image that is 1500 x 500px, some have found that the optimal size seems to be 1500 x 421px.