The format of the image file needs to be either jpeg, png, or gif and the file cannot exceed 10 MB in size. We recommend a logo of 280px (width) and 140px (height). The logo will be resized to a max width of 300px and a max height of 100px if it exceeds either.
To change the logo:
The logo is shared between pages and emails, so you only have to upload it once.
Go to the Emails & Pages page of your dashboard and click Edit on the theme you wish to edit.
You'll be taken to the Branding tab where you will see options to Reset or Upload a logo.
Click Upload Logo, and select or drop the file you wish to use. You have the option to crop, circle, or rotate the image uploaded to the dashboard. Once you are done, click on Upload.