The ideal image size will depend on where you intend to use it, and the desired distribution method. All images should be in GIF, JPG or BMP format and under 1MB in size.
Header/Banner image: 360px wide and 100px high at minimum. Multiples of this are acceptable and will result in a higher resolution image.
Our platform will force the banner to fit to the width of the screen if the page is being viewed on mobile.
Keep in mind that the taller this image is, the further down the content on your page will be.
Header Background image: There is no recommended size for this. Depending on your image style (pattern that should be repeated, image that cannot repeat or stretch), you may want to consider using it as the header image.
Social Image: 200px by 200px is an ideal size for the social image. This is shown in place of a video thumbnail, and can be used regardless of whether you have a video. If you would prefer to use a video thumbnail, you can leave this blank.
Scratch and Reveal images: Both should be under 320px wide. These images should have the same dimensions and resolution.
Background image: Depends on if you want your background image to repeat, stretch, or not.
Other images: All images need to be in one of the formats specified above, as well as under 1MB. Depending on what the intent of the image is (call to action, link to maps, etc) the best way to work out your ideal size is often trial and error.