Summary: DAY TO SEND EMAIL CAMPAIGNS guys it is different across lists industries and many other factors but I am hoping to see a few more companies give some new ideas a try in the inbox One other thing it looks like is that they are learning what is working when trying these formats out I have seen PLUS 2700 pixel wide formats too big for Outlook and now this one is 1550
Image Dimensions: 1550 x 700
Image originally found here.