Your cat may never give up your secrets. But your cat photos might.

Using cat pictures — that essential building block of the Internet — and a supercomputer, a Florida State University professor has built a site that shows the locations of the cats (at least at some point in time, given their nature) and, presumably, of their owners.

Owen Mundy, an assistant professor of art who studies the relationship between data and the public, created “I Know Where Your Cat Lives” as a way of demonstrating “the status quo of personal data usage by startups and international megacorps who are riding the wave of decreased privacy for all,” Mr. Mundy wrote in a post about the site.

Using images of cats uploaded to photosharing services, including Flickr, Twitpic and Instagram, Mr. Mundy extracted latitude and longitude coordinates that many modern cameras, especially those in smartphones, attach to each image. His site displays random images from a sample of one million of the many millions of pictures tagged with the word “cat” online.

The images are displayed on a map using satellite imagery, with nearby cat photos also visible. Specific street addresses are not displayed, but the geographic information can leave few details to the imagination in rural areas.