Redact image — black out sensitive areas
Draw a solid black box over part of an image to redact it. It runs entirely in your browser using canvas (0 uploads, works offline) — your file never leaves your device.
How to use it
- Choose an image and set the box position and size.
- Adjust the options.
- Download the result.
FAQ
How do I do this for free?
Choose the image and enter the box X, Y, width and height to cover, and this page draws an opaque black box — on your device with no upload, no watermark and no account.
Is my file uploaded anywhere?
No. Everything happens in your browser and nothing is transmitted or stored, which you can verify by turning off your Wi-Fi. That is the whole point of an on-device tool.
Why does on-device processing matter here?
Your files stay private — nothing is sent to a server, so nothing can be logged, cached or leaked, and it keeps working offline.
What formats are supported?
Common image formats; output is a PNG that truly removes the pixels under the box.
Limits
Runs in the browser, so very large files are limited by your device's memory; output is a standard image or file.
Related
The signature extractor isolates ink; the EXIF remover strips metadata.
Bookmark this page (Ctrl+D, or ⌘D on Mac) or install the app — it works offline the next time you need it.