There are many laws in the physical sciences, most of which have mathematical equations that govern them. Widely know laws such as the laws of electricity and magnetism, have Maxwell’s equations. Fluid-flow is governed by the Navier-Stokes equations, and of course everyone is familiar with Einstein’s energy to mass relation, E=mc2. Why then does an equally relevant and useful law, Murphy’s Law, have no such foundational equation? In what follows I present an equation to predict the outcome of Murphy’s Law. The law, in its simplest form, states: “If anything can possibly go wrong, it will, and at the worst…