Your Coast FIRE number today.
Coast FIRE number (needed today)
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Retirement target (future)
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The moment you can stop saving and still retire on time
Coast FIRE is one of the more liberating ideas in personal finance. It is the point at which the money you have already invested is enough, on its own, to grow into your full retirement target by the time you stop work, with no further contributions at all. You still need a job to pay this year's rent and groceries, but you are off the savings treadmill. Every dollar beyond living costs becomes genuinely yours to spend. This calculator finds the lump sum you would need invested today to be in that position, and tells you how far short you are.
Two pieces of arithmetic doing the work
The tool works backwards in two steps. First it sets your retirement target by dividing your desired annual spending by your withdrawal rate, the familiar safe-withdrawal logic where a 4 percent rate implies a portfolio 25 times your spending. Then it discounts that future target back to today using your expected real return over the years until retirement. Because the return here is a real return, already net of inflation, the answer is in today's dollars, which is what makes it intuitive to act on.
A 35-year-old aiming to coast to 60
Run the defaults. Spending of $60,000 at a 4 percent withdrawal rate gives a retirement target of $1.5 million. With 25 years until retirement at age 60 and a 6 percent real return, that $1.5 million discounts back to about $349,498 needed invested today. With $200,000 already invested, the gap to Coast FIRE is roughly $149,498. Cross that line and you could, in theory, never contribute another dollar and still arrive at $1.5 million by 60.
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The curve below shows the $349,498 coasting up to $1.5 million on compounding alone. The steepening shape late on is why reaching the number early is so powerful.
Coast FIRE in an Australian super system
There is a uniquely Australian wrinkle here. A big slice of most people's retirement money sits in superannuation, which they cannot touch until preservation age, currently 60 for anyone born after mid-1964. That actually helps the Coast FIRE case. Your employer is legally required to pay 12 percent of your wage into super, so even after you decide to coast, contributions keep flowing in whether you like it or not. Many Australians effectively reach Coast FIRE inside super without realising it, because the compulsory guarantee plus early-career balances do the heavy lifting. If your retirement target is mostly inside super, set your retirement age at or after 60 so the money is actually accessible when the projection says it arrives.
Be honest about the real return
The single assumption that swings this result most is the real return. Dropping it from 6 percent to 5 percent lifts the lump sum you need today by tens of thousands, because the gap compounds over decades. Australian and global equities have historically returned around 6 to 7 percent above inflation over long periods, but there is no guarantee, and a portfolio with bonds or held inside a conservative super option will earn less. Use a return that matches how your money is genuinely invested, not the best year you ever had, and treat the figure as a target to revisit, not a promise.
Questions people ask about coasting
How is Coast FIRE different from full FIRE?
Full FIRE means your portfolio covers your living costs now, so you can stop working entirely. Coast FIRE only means your invested money will grow into that figure by retirement, so you still work to cover today's expenses but no longer need to save. Coast FIRE arrives years, sometimes a decade or more, before full FIRE.
If I keep contributing after reaching the number, what happens?
You retire earlier, or richer, or both. The Coast FIRE number is a floor, not a ceiling. Continuing to invest pulls your achievable retirement date forward or lifts the final balance above target, giving you a buffer against weaker returns than assumed.
What withdrawal rate should I use?
Four percent is the common starting point, drawn from long-run studies of sustainable withdrawals, and it implies a target of 25 times spending. If you are cautious, or retiring young with a long horizon, a 3.5 percent rate is more conservative and lifts the target. The lower the rate you choose, the larger the nest egg you are aiming at.