Make any song swing

Swingify attempts to turn any song into a swing version of itself. Upload an audio file, select the hardness of swing you prefer, and listen.

Here are some of the potted examples:

I uploaded Morrissey's Spring-Heeled Jim (for no greater reason than that the result could be named Swing-Heeled Jim) and am surprised by how much energy it adds: Swing-Heeled Jim.