Canvas prints are available in numerous sizes as gallery wraps on ready-to-hang frames. For canvases, part of the image will "wrap" around the wooden frame. You have to be aware of the cropping margin so that you are not losing important parts of the image. You are able to adjust the crop when you are reviewing your Shopping Cart by clicking on the Edit Crop link under each image.
For example, if you are using WHCC as your lab, you will want to allow an extra 2" to each side for a total of 4 extra inches to your final image size. An 8x10 gallery wrap canvas will actually print the image at 10x12 and the other 2 inches will be wrapped around the frame and not visible from the front.