Our free FIRE Calculator helps you work out when you could reach financial independence and retire early. Answer five quick questions to see your personal FIRE number, along with an inflation-adjusted estimate of when you could get there.
Your answers — tweak any number and update
Your “FIRE number” is calculated using the common 4% rule — 25 times your annual spending — a widely used estimate for how much you’d need invested to live off safely without earning a salary. To keep things meaningful, we adjust your expected return for inflation (assumed at 2.5% a year, the UK’s long-term average), so every figure here is shown in today’s money rather than inflated future pounds. This is an illustration only, based on a fixed rate of return applied consistently; real returns vary year to year. This is not financial advice.
FIRE Calculator FAQs
What is the 4% rule and my "FIRE number"?
The 4% rule is a widely used guideline suggesting you can safely withdraw 4% of your investments each year without running out of money. That means your FIRE number, the amount you'd need invested, works out to roughly 25 times your annual spending. Read our full What Is FIRE? guide for more detail.
Does this account for inflation?
Yes. We convert the return you enter into a "real" return after subtracting an assumed 2.5% UK long-term inflation rate, so your results are shown in today's spending power rather than inflated future pounds.
What if I don't reach my FIRE number in the results?
If your numbers would take more than 60 years, we don't show an unrealistic figure, we show a message instead. Try increasing your monthly investment, adjusting your expected return, or lowering your target annual spending to see how it changes your timeline.
Is my information stored anywhere?
No. Every calculation happens entirely in your own browser, we don't see, collect, or store any of the numbers you enter. See our Privacy Policy for more detail.