Back when newspapers ruled the earth (yes, I’m unconsciously trying to make print media sound prehistoric), The Fold was a physical crease in the paper. Nowadays it’s a bit more complicated. You have different screen sizes and resolutions, toolbars that take-up room in the browser, and some people resize their browser window differently… There are a lot of factors.

FoldSpy is an interesting little bit of JavaScript magic that let’s you see where the fold is on people’s computers. Once you place the script on your site, you activate it by visiting http://yourdomain.com/#foldspy. An interactive overlay appears, allowing you too see what parts of your site are visible above the fold by different people. As you adjust the overlay, you’re shown a percentage based calculated by the viewport size data collected from all of the sites that use FoldSpy.