How to use this Coast FIRE calculator
- Enter your age, the age you want to fully retire, your super balance and what you have invested outside super.
- Enter what you invest each month outside super, your salary now, and the salary you expect while coasting. Both drive employer super.
- Set your yearly retirement spending in today's dollars. Optionally add your own Age Pension estimate and adjust the assumptions.
Results update as you type. Copy the share link to save a scenario, or download the projection for both pots as a CSV.
What is Coast FIRE in Australia?
Coast FIRE is a stage of financial independence where your investments are big enough to grow into a full retirement fund by your target age without new savings from you[8]. You keep working, but only to pay today's bills, so you can take a lower-paid job, cut your hours or take time out.
Two Australian rules change how the number works. First, the super guarantee: if you coast in a job as an employee, your employer still pays 12% of your qualifying earnings into super[1]. Most Coast FIRE maths assumes contributions stop completely when you stop saving; yours keep coming. Second, preservation age: super cannot pay for anything before 60, so if you plan to fully retire earlier, part of your coast number must sit outside super.
How is the Australian Coast FIRE number calculated?
The calculator starts from your target at retirement: yearly spending ÷ your withdrawal rate, reduced for an Age Pension if you include one. Then it subtracts what the super guarantee on your coasting salary will grow to by then, and discounts the rest to today at your real (after-inflation) return:
Coast FIRE number = (target − future value of coasting super contributions) ÷ (1 + real return)years to retirement
Employer contributions are counted after the 15% tax the fund pays on concessional contributions[2]. If you retire before 60, there is a second test: the money outside super must grow into enough to fund every year until super unlocks.
Worked example
Sam is 30, wants to retire at 60 and plans to spend $50,000 a year. With a 7% expected return, 3% inflation and 0.1% fees, the real return is 3.79%. Sam plans to coast in a job paying $60,000, which puts $6,120 a year into super after contributions tax.
- Target at 60: $50,000 ÷ 4% = $1,250,000
- The coasting super guarantee grows to $331,246 by 60, so investments today only need to grow into $918,754.
- Coast FIRE number: $918,754 ÷ (1.0379)30 = $301,290, compared with $409,917 with no super guarantee.
Sam has $80,000 in super and $40,000 in ETFs, and earns $90,000 now. Investing $1,500 a month outside super on top of the employer contributions, Sam reaches Coast FIRE at 41. From then on Sam could stop saving entirely and, if returns match the assumption, still have $1,250,000 at 60.
Coast FIRE numbers by age
The earlier you reach your number, the smaller it is, because the money has longer to compound and more years of employer contributions follow. For Sam's plan, retiring at 60 on $50,000 a year:
| Your age | Coast number with $60,000 coasting salary | Coast number with no employer super |
|---|---|---|
| 25 | $222,788 | $340,403 |
| 30 | $301,290 | $409,917 |
| 35 | $395,823 | $493,626 |
| 40 | $509,661 | $594,430 |
| 45 | $646,746 | $715,818 |
The gap between the columns is the value of the super guarantee while you coast. It is largest when you start coasting young, because those contributions have decades to grow.
What if you want to retire before 60?
Preservation age is 60 for anyone born on or after 1 July 1964[3]. If Sam wanted to fully retire at 55 instead, the five years from 55 to 60 would need $237,273 outside super on the day Sam stops work. Discounted to today, that means at least $93,699 of Sam's coast number has to be outside super at 30, and the total rises to $395,823 because there are five fewer years of growth and employer contributions.
With the same savings, Sam would reach Coast FIRE for a 55 retirement at 49. Coasting to 60 or later avoids the problem, because both pots are available on the day you retire.
When can you take your super after coasting?
Coast FIRE often means working part-time into your 50s or 60s, which fits Australia's release rules well. Once you are 60, ending any employment arrangement counts as retirement, even a small job. If you stopped work before 60, you meet the retirement condition at 60 when your fund is satisfied you never intend to work 10 hours or more a week again. At 65 your super is released whether or not you still work[3]. Super benefits received at 60 or older are tax-free for the great majority of members[4].
How does the Age Pension change your Coast FIRE number?
Age Pension age is 67 for anyone born on or after 1 January 1957, and the amount depends on an income test and an assets test[5]. Super is not counted as a financial investment for those tests until you reach Age Pension age, but after that it is[5], so someone who coasts to a large balance may get little or no pension.
If you expect some pension, enter your own estimate. For Sam, $15,000 a year from 67 lowers the target at 60 from $1,250,000 to $973,640 and the coast number at 30 from $301,290 to $210,662. The pension pays nothing between 60 and 67, so those years still come from your own money.
Coast FIRE for couples in Australia
Super is held in each person's name and each partner reaches preservation age based on their own date of birth[3], so a couple has two locks, not one. For a quick household answer, enter combined balances and spending, use the younger partner's age, and enter both coasting salaries added together. That is cautious: the younger partner's super unlocks last. If one of you will coast without an employer, for example while caring for children or running a business, leave that salary out, because no super guarantee will be paid on it.
What return and inflation should you assume?
The coast number is very sensitive to the return, because it compounds over decades. The defaults are 7% before inflation, 3% inflation and 0.1% fees. The Reserve Bank's target is inflation between 2 and 3 per cent[6], and headline inflation was 3.9% over the year to the September quarter 2026[7]. Vanguard's 10-year forecast for developed markets outside the US is 5.3%-7.3% a year[12], below the 10.0% US shares returned from 1928 to 2025[11]. The table in the calculator shows your coast number at real returns from 3% to 7%, so you can see how much a cautious assumption costs.
The withdrawal rate sets the target. 4% comes from Bengen's study of 30-year US retirements[9]; if your retirement could run 40 years or more, research points to 3.25%-3.5%[10].
What if markets disappoint after you coast?
This is the real risk of Coast FIRE. Once you stop saving you can no longer buy when prices are low, and the returns in your first decade of retirement largely decide how much you can safely spend[13]. The risk section runs 2,000 simulations and replays every retirement start year since 1928, starting from the age you begin coasting, with your employer contributions still coming in.
Those tests use US share, bond and inflation history[11], not Australian data. Other markets have had different, often weaker, histories, so treat a high success rate as encouraging rather than certain. If the result is lower than you would like, coast a few years later, keep a small monthly contribution going, or plan on part-time work after 60. The Australian FIRE calculator shows how much earlier you could stop work altogether if you keep saving.