Remove Image Backgrounds

What the cut-out is made of

The cut-out is decided by what things are rather than by texture, and that distinction is the whole difference on the photos people complain about: a tool that goes by texture, pointed at a glass of water, sees the backdrop through the water, calls it background and leaves a hole where the liquid was, and returns a flat-coloured shirt half transparent. This one returns the glass solid. What it gives up is sharpness — the first pass works at a reduced size and that verdict is stretched over your full-size photo, so fine structure arrives soft rather than crisp, which is what the cleanup below exists to fix.

Then there is a full-resolution cleanup that most cut-out tools do not bother with. It measures how soft this particular mask is before deciding what counts as background — a mask whose detail is genuinely half-transparent, like a head of flyaway hair, is read on its own terms rather than against a fixed threshold that would dismiss every strand as haze. It then fills the mid-alpha deep inside a subject (that is the tool being uncertain, not the shirt being see-through), deletes disconnected patches of haze, and finally un-mixes colour along the boundary. Edge pixels genuinely contain the old background, because the camera mixed it into them; each one is corrected against the local backdrop colour it came from, which is why hair does not glow with the colour of the room when you drop it onto something else.

What you download follows from that. The alpha is continuous rather than a one-bit mask, so the cut-out composites properly over anything. Download PNG gives you a palette-quantised PNG — 256 dithered colours, alpha included — because a lossless RGBA export of a twelve-megapixel photo runs to about ten times the JPG it came from, and this is still an ordinary PNG that opens anywhere. The compact download is a WebP while the background is transparent and a JPG once you place the subject on a colour, since a solid background needs no alpha at all.

When you want something else

There is no brush. When it gets something wrong — glass, smoke, chain-link fence, motion blur, a subject the same colour as the wall behind it — you cannot paint the correction in, and running it again produces the same answer. GIMP's free select with a layer mask, or Photoshop's Select Subject followed by Select and Mask, will fix in a minute what no amount of re-running fixes here.

It is also one photo per click, after a first-use download of 93 MB — and a device that cannot hold that, a small phone or a browser set to save data, gets nothing here at all. For a hundred product shots, rembg is a free command-line program that does the same job: point it at a folder, come back later, and nobody has to sit and click.