RunwayMath

RunwayMath is a mobile + web app (traditional app with light AI) that stress-tests early-retirement plans against reality: taxes, healthcare, sequence-of-returns risk, and lifestyle creep. Users link accounts (or enter balances manually), select a target location and retirement age, and the app runs thousands of Monte Carlo simulations with configurable assumptions. The core output is a “Runway Score” showing probability of success, worst-case drawdowns, and the exact spending level that keeps risk acceptable. A lightweight AI layer turns results into plain-English actions: cut spending by X, delay retirement by Y months, shift allocation, or build a cash buffer. It also includes a “Bad Year Playbook” that tells users what to do if markets drop 30% right after quitting. It won’t promise certainty; it will show tradeoffs clearly and repeatedly.