We’ve had an amazing response to our launch. But one question has cropped-up again and again: where does the FoldSpy data come from and how accurate is it? So I think it’s time to explain that a little better.
Where does it come from?
FoldSpy Free uses data collected from sites of other FoldSpy Free users. When it’s installed on a site, it measures the browser window dimensions of every 3rd visitor. It does all of this quickly and quietly in the background, just like any other good stats software. Every night the data is collected, processed and fed back into the FoldSpy Free system.
How accurate is it?
Our users come from all corners of the globe, with a wide array of sites: from personal blogs to international media outlets. So we’re happy our data is very accurate. But as time goes on, the FoldSpy data will get even more precise.
How fresh is it?
On top of this, we ensure our data is fresh by pruning records older than 30 days. This means you can use FoldSpy Free to watch global trends.
Time for transparency
Since the quality of the data itself is key to the value of FoldSpy Free, we think it’s time to open up and give you a better understanding of what’s going on. So we’ve made changes to our site, and more importantly to FoldSpy Free itself, to show you just how many browser screens we’ve measured and from how many sites. As I type, we’re at 2,287,540 browser screens measured on 1,360 sites!

Where does FoldSpy Pro come in?
Most people will be happy with the data they get from FoldSpy Free. It provides a very accurate, general view of browser sizes around the globe. But since the visitor profile of every site is different (for example, sites used by designers will, in general, be viewed with much larger screens), the only way to get truly accurate, personalised data, is to use FoldSpy Pro. FoldSpy Pro gives you everything you get in Free, but also records data directly from your site, for every visitor, displaying it separately from the global data. FoldSpy Pro is for… pros!