While you may be thinking your email needs a bit more room to add one more picture, you can't adjust the width of the emails, that's already been built in. It's really in your best interest to trust us here, we've been sending emails for a long time. You might want to increase the width of your email to fit your screen, but not all screens have the same dimensions, which might force your readers to scroll left and right to see the email. Scrolling can be confusing and your readers might even miss some of the content in your message.
All of our templates are sized to display well across email clients. The templates are also responsive, which means that they automatically adjust for display on mobile devices as well. Pretty cool, right?
If you need to add more content, use more content blocks below your existing content, instead of trying to make the email wider.