№ 033 · Retirement cluster
Coast FIRE Calculator
Coast FIRE is the moment you’ve saved enough that you can stop saving — compound growth alone will carry what you already have to your full retirement number. This calculator finds the amount you need invested today to coast, and shows whether you’re already there.
Coast number · projected balance · already-coasting check
Still saving toward the finish line? The Retirement / FIRE Calculator solves for the years to full FI with ongoing contributions, and the Investment Growth Calculator projects a portfolio you keep funding. Already retired? See how long the balance lasts with the Retirement Withdrawal Calculator.
Your target01
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%
Where you stand02
yr
yr
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Growth03
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Coast FIRE reached — you can stop contributing
$1,141,838.26
what your $150,000.00 coasts to by age 60 · coast number $131,367.12
$18,632.88 past your goalFIRE number $1,000,000.00Hits your goal at age 59
Coast FIRE number$131,367.12
Currently invested$150,000.00
FIRE number$1,000,000.00
Surplus today$18,632.88
- Balance$1,141,838.26
- Contributed$150,000.00
- FIRE number$1,000,000.00
| Year 0 | balance $150,000.00, contributed $150,000.00 |
|---|---|
| Year 1 | balance $160,500.00, contributed $150,000.00 |
| Year 2 | balance $171,735.00, contributed $150,000.00 |
| Year 3 | balance $183,756.45, contributed $150,000.00 |
| Year 4 | balance $196,619.40, contributed $150,000.00 |
| Year 5 | balance $210,382.76, contributed $150,000.00 |
| Year 6 | balance $225,109.55, contributed $150,000.00 |
| Year 7 | balance $240,867.22, contributed $150,000.00 |
| Year 8 | balance $257,727.93, contributed $150,000.00 |
| Year 9 | balance $275,768.88, contributed $150,000.00 |
| Year 10 | balance $295,072.70, contributed $150,000.00 |
| Year 11 | balance $315,727.79, contributed $150,000.00 |
| Year 12 | balance $337,828.74, contributed $150,000.00 |
| Year 13 | balance $361,476.75, contributed $150,000.00 |
| Year 14 | balance $386,780.12, contributed $150,000.00 |
| Year 15 | balance $413,854.73, contributed $150,000.00 |
| Year 16 | balance $442,824.56, contributed $150,000.00 |
| Year 17 | balance $473,822.28, contributed $150,000.00 |
| Year 18 | balance $506,989.84, contributed $150,000.00 |
| Year 19 | balance $542,479.13, contributed $150,000.00 |
| Year 20 | balance $580,452.67, contributed $150,000.00 |
| Year 21 | balance $621,084.36, contributed $150,000.00 |
| Year 22 | balance $664,560.26, contributed $150,000.00 |
| Year 23 | balance $711,079.48, contributed $150,000.00 |
| Year 24 | balance $760,855.04, contributed $150,000.00 |
| Year 25 | balance $814,114.90, contributed $150,000.00 |
| Year 26 | balance $871,102.94, contributed $150,000.00 |
| Year 27 | balance $932,080.14, contributed $150,000.00 |
| Year 28 | balance $997,325.75, contributed $150,000.00 |
| Year 29 | balance $1,067,138.56, contributed $150,000.00 |
| Year 30 | balance $1,141,838.26, contributed $150,000.00 |
Year by year · coasting
| Year | Age | Coasting balance | Gap to FIRE |
|---|---|---|---|
| 0 | 30 | $150,000.00 | $850,000.00 |
| 1 | 31 | $160,500.00 | $839,500.00 |
| 2 | 32 | $171,735.00 | $828,265.00 |
| 3 | 33 | $183,756.45 | $816,243.55 |
| 4 | 34 | $196,619.40 | $803,380.60 |
| 5 | 35 | $210,382.76 | $789,617.24 |
| 6 | 36 | $225,109.55 | $774,890.45 |
| 7 | 37 | $240,867.22 | $759,132.78 |
| 8 | 38 | $257,727.93 | $742,272.07 |
| 9 | 39 | $275,768.88 | $724,231.12 |
| 10 | 40 | $295,072.70 | $704,927.30 |
| 11 | 41 | $315,727.79 | $684,272.21 |
| 12 | 42 | $337,828.74 | $662,171.26 |
| 13 | 43 | $361,476.75 | $638,523.25 |
| 14 | 44 | $386,780.12 | $613,219.88 |
| 15 | 45 | $413,854.73 | $586,145.27 |
| 16 | 46 | $442,824.56 | $557,175.44 |
| 17 | 47 | $473,822.28 | $526,177.72 |
| 18 | 48 | $506,989.84 | $493,010.16 |
| 19 | 49 | $542,479.13 | $457,520.87 |
| 20 | 50 | $580,452.67 | $419,547.33 |
| 21 | 51 | $621,084.36 | $378,915.64 |
| 22 | 52 | $664,560.26 | $335,439.74 |
| 23 | 53 | $711,079.48 | $288,920.52 |
| 24 | 54 | $760,855.04 | $239,144.96 |
| 25 | 55 | $814,114.90 | $185,885.10 |
| 26 | 56 | $871,102.94 | $128,897.06 |
| 27 | 57 | $932,080.14 | $67,919.86 |
| 28 | 58 | $997,325.75 | $2,674.25 |
| 29 | 59 | $1,067,138.56 | $0.00 |
| 30 | 60 | $1,141,838.26 | $0.00 |
How it works · methodology
The math, in the open.
FIRE number = annual expenses ÷ (withdrawal rate ÷ 100) years = retirement age − current age coast number = FIRE number ÷ (1 + r)^years projected = current invested × (1 + r)^years coasting when current invested ≥ coast number
- r
- Expected real (after-inflation) annual return
- years
- Years from now until your retirement age
- withdrawal rate
- Safe withdrawal rate (4% rule → 25× expenses)
- FIRE number
- Nest egg needed at retirement, in today’s dollars
Assumptions & limits
- Everything is in today’s dollars using a real, after-inflation return; no separate inflation input is needed.
- The coast projection assumes zero further retirement contributions — only growth of what you already have.
- Returns are modeled as a steady annual rate; real markets vary year to year, so treat the result as a planning estimate.
- The FIRE number uses your chosen withdrawal rate; a lower rate is safer but raises the target. Not investment advice.
By the MintNumber Editorial Team·Reviewed
Frequently asked
Questions about Coast FIRE
What is Coast FIRE?
Coast FIRE is the point where you have enough invested that you no longer need to save another dollar for retirement — compound growth alone will carry your existing balance to your full FIRE number by the time you retire. You still have to cover your living expenses, but you can stop contributing to retirement accounts and let the portfolio "coast." Your Coast FIRE number is the amount that needs to be invested today to make that happen.
How is Coast FIRE different from regular FIRE or the retirement calculator?
Regular FIRE asks "how many years until I have enough to live off my portfolio?" — our retirement calculator answers that given your ongoing contributions. Coast FIRE asks the reverse: "how much do I need invested right now so I can stop saving and still hit my number on schedule?" Coast FIRE almost always happens years before full FIRE, because you are letting decades of compounding finish the job instead of saving your way there.
How is the Coast FIRE number calculated?
First we find your FIRE number — annual expenses divided by your withdrawal rate (the 4% rule gives 25× expenses). Then we discount that target back to today using your expected real return over the years until retirement: coast number = FIRE number ÷ (1 + real return)^years. If your current balance is above that figure, you have reached Coast FIRE. Everything is in today’s dollars using a real, after-inflation return, so you don’t need a separate inflation input.
What real return should I use?
The "real" return is what your portfolio earns after subtracting inflation. A diversified, stock-heavy portfolio has historically returned roughly 6–7% per year after inflation over long periods, but that is an average across very good and very bad decades — there is no guarantee. Using a lower figure (say 4–5%) builds in a margin of safety; using 7% is optimistic. Because the coast number is highly sensitive to this number, it is worth testing a range.
If I hit Coast FIRE, should I really stop investing?
Coast FIRE is a milestone, not necessarily an instruction. Reaching it means retirement saving is no longer mandatory — which can free you to take a lower-paying job you enjoy, go part-time, or take a career break. But continuing to invest pulls your retirement date earlier or raises your eventual lifestyle, and it cushions against the years when returns disappoint. Treat it as new optionality, not a hard stop.