While pokerstove does essentially the same calculations, I don't think it has a web interface. My goal was to make an easy to use app that didn't require you to install anything or have any programming background. But thanks for the note, and I can definitely use pokerstove in the backend to run faster simulations.
Thank you! The api looks really useful, and I'll see if I can add it in. The simulations are basically random draws from a deck of cards assuming that the cards inputted have already been drawn. I then just count the wins from the random draws to figure out the probability of winning.