Remove the background from any image

A phone photo is the easy case. It is sharp and large, and the subject usually fills a good part of the frame. HEIC files from an iPhone are read directly, so you can send them as they are. A screenshot behaves differently. It often contains several things of equal weight, a window, some text, a logo, and the tool has to decide which of them is the subject; crop to the part you want before you start and the answer becomes obvious.

A scan of a printed photo carries paper texture and sometimes a border. The border is removed with the background, which is normally welcome. A Photoshop file is read as the flattened picture stored inside it, the one you see on opening the file, so hidden layers play no part.

A transparent PNG stores every remaining pixel exactly, and for a photograph that is expensive. The cut-out of a twelve-megapixel portrait can weigh 8 MB or more as a PNG. The same cut-out as a WebP is typically under 1 MB with the transparency intact, and on a white background as a JPG it is smaller still.

So choose by destination. PNG for design software and print services that ask for it. WebP for anything on the web. JPG with a solid colour for forms, documents and marketplaces. If the file is still too large, put the result through the compressor on this site, which reduces a PNG's colours without touching its transparency.

By default nothing is resized: a picture of 4000 by 3000 comes back at 4000 by 3000 with the background cleared. The product canvases are the exception. Choose 1000 by 1000, 2000 by 2000, 1600 by 2000 or 1200 by 628, and the subject is centred on a canvas of exactly that size, with the same margin all round. Shop platforms and ad systems tend to ask for precisely such fixed sizes, and this spares you a second tool.