Pick a preset and the preview becomes a canvas of exactly that size. Your image is first fitted inside it whole, without cropping, and any empty space is filled with white. From there you can:
- zoom with the slider or the mouse wheel to fill the frame (this crops the edges that fall outside);
- drag the image with a mouse or a finger to choose which part stays in view;
- turn the image left or right in 90 degree steps;
- press Fit Image to return to the whole image centred.
The export is rendered at the preset's full pixel size from your original image, not from the smaller preview, and saved as a WebP file at quality 0.92.