🎲 Stress Test

The Stress Test runs a Monte Carlo simulation, hundreds of randomised market paths, reporting a success rate and a fan of outcomes, plus life-and-care scenarios.

What the walkthrough covers

The Stress Test tab checks whether your plan holds up when things don't go smoothly. Rather than assuming steady returns, it runs your entire plan hundreds of times, each with a different random sequence of market ups and downs and inflation. It then reports a success rate, the percentage of those runs where your money lasts, and shows a fan of outcomes, from a pessimistic tenth-percentile result to an optimistic ninetieth. Importantly, the best and worst cases aren't hand-picked; they emerge from the simulations. Below that comes the named stress battery: specific shocks, each applied to your own plan and re-run through the full engine (a market crash tomorrow, an unexpected twenty-thousand-pound bill, a year without earnings, lower growth, higher inflation, stopping work early, living to a hundred, and care costs arriving early), each judged twice, on your full budget and on essentials alone. And a historical backtest replays your plan through every market sequence since 1928, so you can see which real decades it would have survived. You don't enter anything here: it's built from your existing plan.