How background removal works
After you choose a file, SizeUply loads an on-device U²-NetP model with ONNX Runtime. The model estimates a foreground mask. That mask becomes the PNG alpha channel.
The photo is not sent to an image API. Processing stays in the browser. Results vary. This is not a claim of perfect cuts on every subject.
Supported formats and the download
Add a JPG, PNG, or WebP file. The download is always a transparent PNG named from the original file, such as photo-background-removed.png.
The checkerboard behind the preview is only there so you can see transparency. It is not part of the downloaded file.
Privacy and the model file
Your image stays in this tab. The first visit to this tool may download a few megabytes of model weights from SizeUply so the browser can run locally next time from cache.
Google Analytics, when enabled in production, does not receive the image contents.
Limits
Very large images are reduced so the browser can finish. Hair, smoke, glass, and backgrounds that match the subject are common failure cases.
If the browser cannot run WebGPU or WebAssembly, the tool stops with an error instead of pretending the background was removed.
How to use the tool
Choose an image, wait until the model is ready, then select Remove background. Compare the original and the transparent result. Download the PNG if the cut looks usable, or try a different photo.