Quadkeys are sometimes hard to find

Quadkeys are Bing Maps&rsquo;s way of subdividing a Web Mercator map of the world into tiles. It is a simple quadtree-like system where each tile at a spcific zoom level has exactly four children: I find myself needing to convert map location on earth in longitude / latitude to a Bing quadkey sometimes, and I found there is no easy web tool to do this, so I wrote one: What the Quad :