Adoption is a photo contest with a deadline. A shelter or foster posts the same dog to Petfinder, Adopt-a-Pet and its own website, and each of those places wants a different number: Petfinder accepts JPG, PNG, GIF or BMP up to 25MB and asks for at least 570 pixels wide, Adopt-a-Pet recommends nothing heavier than 2MB and says 100k is usually plenty big, and Rover wants a roughly 400x400 profile shot for the sitter. Uploading a 6MB phone photo to all three wastes minutes per animal when a rescue is posting twenty at once, and the platforms downscale it anyway. Compress once from the original, keep the pixels the platform actually renders, and the listing goes live in one pass. Skwish does this in the browser with a live per-file size readout, a batch queue and a ZIP export, so a whole kennel folder can be resized and compressed at once. Photos never leave your machine, which matters when the subjects are animals in someone else's care.