If your image does not fit the product size, by default we will crop your image centrally. We print the image as large as possible, removing the top/bottom or left/right parts of the image that go beyond the print area.
However, you can also specify a sizing parameter to change this behaviour.
Crop (default): your image will be centred and cropped so that it exactly fits the aspect ratio (height divided by width) of the printing area of the product you chose. Your image will cover all of the product print area.
ShrinktoFit: your image will be resized so that it completely fills the print area of the product, If the aspect ratio of your image is different to that of the printing area, your image will be stretched or squashed to fit.
Our print API will automatically rotate your images so that they need the least possible resizing to fit the product size. For example, if you are creating a 10x15 photo, and upload an image that is 4500x3000px, then we will flip it so it is 3000x4500px and thus fits the photo perfectly.