The pot today that coasts to retirement.
Coast FIRE number
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Full FIRE target
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Still needed today
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Your breakdown
Updates live as you type| Step | Working | KES |
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The moment saving becomes optional
Coast FIRE is a quietly liberating idea. It is the point at which your invested pot is already big enough that, even if you never save another shilling, compound growth alone will carry it to your full retirement target by the time you stop working. You have not retired, you still need to cover today's bills, but the heavy lifting on retirement is done. From that point your salary only has to fund your present life, not your future one. For anyone in Kenya weighing a career change, a startup, or simply more time with family, hitting your coast number is the green light to ease off the savings throttle.
This calculator finds two numbers and compares them. First it sets your full retirement target by dividing your annual expenses by your chosen safe withdrawal rate, the classic way of asking how large a pot you need to live off its returns. Then it discounts that target back to today using your expected real return over the years until retirement, which gives the coast number, the pot you would need right now for growth alone to finish the job. Finally it checks your current savings against that coast number and tells you whether you are already coasting or how much you still need today.
Why this tool uses a real return and no tax line
Unlike the income tax calculators on this site, Coast FIRE is not a Kenya Revenue Authority computation, so there are no PAYE bands or statutory rates baked in here. The lever that matters is the real return, your investment growth after inflation has been stripped out, because retirement planning over decades only makes sense in today's money. The defaults model a 5 percent real return and a 4 percent withdrawal rate, both widely used planning assumptions rather than legislated figures. Tax still matters in the real world, since returns inside taxable accounts are reduced by withholding and other taxes, so a sensible move is to enter a real return that already nets off the tax drag you expect on your particular mix of Saccos, funds and pensions. When in doubt about how an investment is taxed, confirm with the KRA or a licensed adviser.
A 35-year-old planning for 60
Consider someone aged 35 who wants to retire at 60, expects to spend KES 1,800,000 a year in retirement, plans on a 4 percent withdrawal rate, and assumes a 5 percent real return. They have KES 2,500,000 saved so far. Here is how the tool reasons:
So this saver needs roughly KES 13.3 million invested today to coast to a KES 45 million pot at 60, and with KES 2.5 million in hand they are about KES 10.8 million short of the coast number. They are not yet coasting, but the gap is a target, not a verdict. The chart shows the coast number growing untouched to meet the full target.
The assumptions that make or break the number
Coast FIRE is exquisitely sensitive to the real return you choose, because that rate is compounded over decades. Nudge the real return in the example from 5 percent to 7 percent and the coast number falls sharply, since faster growth means you need less today. The honest danger runs the other way. If inflation in Kenya outpaces your nominal returns, your real return could be far lower than assumed, and an over-optimistic figure makes coasting look closer than it is. The fix is conservatism. Use a real return you would be comfortable defending in a bad decade, and treat a coast result as a checkpoint to revisit each year, not a one-time clearance.
The other lever people underweight is the withdrawal rate. A 4 percent rate implies a pot 25 times your annual expenses, while a cautious 3.5 percent pushes that to nearly 29 times, lifting both the FIRE target and the coast number. There is no single correct rate, and the 4 percent guideline came from a different market and era, so think about your own expenses, life expectancy and risk tolerance. A practical tip for Kenyan savers is to express your retirement expenses in today's money and let the real return handle inflation, rather than guessing a future shilling figure, which is exactly the convention this tool follows.
If I have hit my coast number, can I really stop saving?
In theory yes, you can stop saving for retirement once your pot reaches the coast number, because growth alone is projected to reach the target. In practice keep a margin. The projection assumes your real return holds every year, which it will not, so many people keep saving a little longer or treat coasting as permission to take a lower-paid but more fulfilling role rather than to stop saving entirely.
How is Coast FIRE different from the full FIRE number?
Full FIRE is the pot you need to retire today and live off it, which in the example is KES 45,000,000. The coast number is much smaller, KES 13,288,625 here, because it is that same target discounted back over the years your money still has to grow. Reaching the coast number means you can stop adding to retirement savings, while reaching the full FIRE number means you can stop working altogether.