Redact image regions

Draw over sensitive areas to blur or black them out before sharing. No file leaves your device.

How Redact image regions works

Blur or black-box sensitive areas of your images before sharing, faces, ID numbers, addresses, signatures, entirely in the browser. No pixel is ever sent to a server. Draw rectangles over the regions to hide, then download the result.

For truly sensitive data, prefer the black-box option: it paints the region with solid black pixels, permanently destroying the underlying content in the exported file. Blur is visually strong but not cryptographically guaranteed; when in doubt, use the black box.

Frequently asked questions

Are my files uploaded to a server?

No. Your image is processed by the HTML5 Canvas API in your browser tab, it is drawn onto a canvas and opaque boxes are painted over the areas you mark, so the pixels underneath are gone, then exported with toBlob, and the result is offered as a local download. Nothing reaches Sunasty or any third party. Open your browser's DevTools, go to the Network tab and watch: no request carries your image.

Is the black-box redaction truly permanent?

Yes, in the exported image. The black-box option fills the selected region with solid opaque pixels, so there is no hidden layer to recover. The original file on your device is untouched; only the downloaded copy is redacted.

Is blur as secure as the black box?

No. Heavy blur destroys most detail, but determined image-processing techniques can sometimes partially recover content from blurred regions. For sensitive personal data (ID numbers, faces in legal contexts), use the black-box option.

Does it work offline?

Yes, once the page has loaded. Because the processing happens on your device, you can disconnect from the network and the tool keeps working. This is the clearest proof that your data never leaves your machine.

Is it free? Do I need an account?

It is completely free and requires no sign-up. There are no watermarks, no daily limits and no tracking cookies needed to use the tool.

Related tools

Keep everything local, explore complementary tools.