2160x1440 is 3:2 at 2K width, and it is the size Boats Group names as recommended for Boat Trader, YachtWorld and boats.com listings — with 1080x720 as the same-ratio minimum and anything under 1000 pixels flagged as low quality. The number matters because galleries render into a fixed frame. Upload a square phone photo or a tall vertical to a 3:2 gallery and the platform either letterboxes it with dead space or crops into the subject, and neither is under your control. Crop to 3:2 yourself, at the composition you chose, and the platform has nothing left to decide. Two things to get right. First, crop before you resize: forcing a 16:9 or 1:1 original into 2160x1440 by scaling alone stretches the hull or squeezes the wheels, which looks wrong even at a glance. Second, do not upscale — 2160px wide is only useful if the source has the detail to fill it, and a 900px photo blown up to 2160 is a soft 2160. Skwish resizes and compresses in the browser with a live per-file readout and a batch queue, so a whole listing set comes out at one size and one weight in a single pass. Originals stay on your disk.