Obscure: A tool to obscure a certain percentage of an image

This is version 1.0.0 of this application. It has been tested with Safari, FireFox and Chrome on Mac and Windows. It does not work with the versions of Internet Explorer I've tried.

This small web application obscures a certain proportion of an image with little clear squares allowing a background to show through. You can use it in experiments where you want to conceal different proportions of an image (e.g. a logo) and see whether the participant can still tell what the image is.


  1. Drag an image onto the 'Choose File' or 'Browse…' button.
  2. Type appropriate values into the size and percentage fields.
  3. Hit the 'Try again' button until it comes up with an obscured image you like.
  4. Drag the output image into a folder.
  5. Rename the image file to something useful (making sure to keep the ".png" at the end of the filename).

Input area

Drag an image onto this button →

Size of squares: pixels. Proportion of image to show: %.

Output area