Are you looking for the pixel size needed for images in your email? If so the good news is we have this article in our Help Center that shares different tips for preparing your images to be uploaded. One of these suggestions is to not upload an image larger than 600 pixels wide and 1728 pixels in height. However if it is not the pixel sizes of images you're trying to add into an email please let us know! Any clarification you can provide on what you are looking to accomplish can help make sure we are sharing the best information for you.