Retirement / FIRE Calculator

Financial independence is defined by expenses, not income. Your FIRE number is simply the portfolio large enough that a sustainable withdrawal covers your annual spending — under the 4% rule, twenty-five times that spending. Cutting annual expenses therefore does double duty: it raises how much you save each year and lowers the target you are saving toward.

That is why savings rate dominates this calculation. Someone saving half their income reaches independence in a fraction of the time of someone saving a tenth, almost regardless of the return assumption. Try holding income constant and moving the expenses slider — the finish line moves far more than it does when you change the return by a point.

Sequence-of-returns risk is the main thing this model cannot show. A severe market decline in the first years of retirement damages a portfolio far more than the same decline later, because withdrawals lock in the loss. Common responses include holding a cash buffer, keeping flexible spending, or targeting a lower withdrawal rate than 4%.

Coast FIRE is the point where your existing portfolio grows to your target without further contributions — you only need to cover living costs from income. Barista FIRE pairs a smaller portfolio with part-time work. If you retire before pensions unlock, plan a bridge account, and budget for healthcare years that are fully self-funded.