How it works
How the cut-out is made
A portrait-matting model (MODNet, Apache-2.0 licence) looks at the photo and returns a matte: one grey value per pixel saying how much of it belongs to the subject. White is kept, black is removed, and greys along hair and edges give soft transitions.
The matte is scaled back to the size of your original and written into the alpha channel, so the colours of the kept pixels are never changed.
alpha = matte × original alpha ÷ 255
Transparent or on a colour
Transparent saves a PNG with an alpha channel. Colour blends the subject over a flat colour of your choice, which is handy for passport-style photos or product shots that need a plain backdrop.
The file is named after your photo with -no-background.png added.
The model download
The model is not part of this site. On first use it is downloaded from the Hugging Face hub (about 25 MB) and cached by your browser, so later photos start straight away. It runs on the GPU through WebGPU when the browser has it, and on the CPU otherwise, which is slower.
