Calculator
FIRE Number Calculator (Australian Edition)
FIRE Number Calculator (Australian Edition)
Spending in FIRE
Rental income, part-time work or other income that reduces the amount your portfolio must fund.
Where You Are Today
Shares, ETFs, savings and other investments you could access before preservation age.
60 for anyone born after 1 July 1964 — super can only be accessed after this age (subject to a condition of release).
Savings & Assumptions
Your FIRE Number
$1,500,000
FIRE Analysis
Your FIRE number is $1,500,000 and the current plan reaches it in about 29 years. That is a long runway, but compounding does most of the heavy lifting: of the final $3,077,166.06 portfolio, the majority comes from investment returns, not contributions. Stress-test with a lower return or higher inflation to see how sensitive the timeline is before locking in a retirement date.
Educational tool. Estimates only — the calculator assumes the same return every year and does not model sequence-of-returns risk, taxes on non-super investments, or future changes to superannuation law. It does not take the Age Pension into account. Not financial advice; consider advice from a licensed professional before making retirement decisions.
What Your FIRE Number Actually Is
FIRE — Financial Independence, Retire Early — is the point where your investments generate enough income to cover your living expenses, so work becomes optional. Your FIRE number is the portfolio size that makes that possible: your annual spending divided by a sustainable withdrawal rate. The classic 4% rule, drawn from research on long historical returns, says a broadly diversified portfolio worth 25 times annual spending can fund a retirement with a high probability of lasting 30-plus years. In Australia the equation has a twist most overseas calculators ignore: superannuation. A large share of an Australian FIRE portfolio is locked in super, where it cannot be accessed until preservation age — 60 for anyone born after 1 July 1964 — and then only upon a condition of release like retiring. So an Australian must fund two phases: the years from quitting work to 60 out of accessible investments, and the years after 60 from accessible investments plus super. This calculator is built around that structure. It splits your assets into accessible and super, models both growing, and shows whether, and when, the combined pot can cover your spending at your chosen withdrawal rate. The result is a FIRE number and a timeline grounded in the Australian system rather than imported verbatim from US blog math.
How the Calculation Works
The core formula is the withdrawal-rule inverse: FIRE number equals net annual spending divided by the safe withdrawal rate, both expressed in today's dollars. A $70,000 annual spend at a 4% rate requires a $1,750,000 portfolio in today's terms. Net spending is annual household spending minus any income you expect after quitting (rental income, part-time work). To find when you reach the number, the calculator projects your accessible portfolio forward by adding contributions monthly and compounding at the expected return, while the super balance compounds at the same nominal rate. Each year the spending requirement inflates at your chosen inflation rate, so the target itself rises: reaching a $1 million number in 20 years means reaching roughly $1.6 million in nominal terms at 2.5% inflation. The simulation stops the first year the combined accessible-plus-super portfolio equals or exceeds that year's inflation-adjusted target. Both progress bars compare today's assets against today's target. If contributions and returns never outpace an inflating target within the horizon, the tool tells you the plan does not reach FIRE at all — a result that is useful early enough to change course.
Expert Insights
The Super Preservation Gap Is the Australian FIRE Problem
Most Australian wealth sits in super, but super is locked until preservation age. If you leave work at 50 you need your accessible portfolio to fund ten years of spending on its own before super unlocks. Run this calculator with the super balance set to zero to stress-test that bridging portfolio — many FIRE plans that look comfortable on combined assets turn out to be dangerously thin on accessible cash.
Pick the Withdrawal Rate for YOUR Horizon
The 4% rule was designed for 30-year retirements starting at 65. Retiring at 50 means a 40-year-plus drawdown, where researchers generally prefer 3–3.5%. Retiring at 58 with super and a modest Age Pension backstop can justify 4–4.5%. The 1% spread between 3.5% and 4.5% changes the required portfolio by roughly 25%, so this single assumption deserves more care than any other.
Savings Rate Beats Everything
Over the years to FIRE, the contribution rate is the dominant driver — more powerful than tweaking the expected return, which you cannot control. Every extra dollar saved works twice: it adds to the portfolio and it proves a lower spending need when retired. Financial planners often say cutting expenses by $1,000 a year is worth roughly $25,000 of portfolio at a 4% rate; raising income and saving it has the same effect.
Actionable Tips
- 1
Measure Real Spending Before Setting the Number
Pull 12 months of bank and card statements and total true household spending — including infrequent costs like insurance premiums, car rego, travel and dental. Guessing low is the most common FIRE failure. Use that real number, not a budget aspiration, as the annual spending input.
- 2
Build the Bridging Portfolio First
If you plan to quit before 60, treat your accessible investments as a separate goal: annual spending times the years from quitting to preservation age, plus normal market-risk buffer. Salary sacrifice boosts super (taxed at a generous 15% and effectively 0% on exit), but only accessible savings — shares, ETFs, term deposits — can pay the rent at 52.
- 3
Re-run With a Bad Year Baked In
Once you have a target, drop the expected return 1–2% and raise inflation 0.5–1%. If the timeline blows out past acceptable, increase the savings rate or soften the spending plan. A plan that only works under sunny assumptions has no safety margin, and the first decade of early retirement is exactly when sequence-of-returns risk is highest.
Real-World Examples
Sarah's Two-Pot Plan at 29
Sarah, a 29-year-old engineer in Melbourne, spends $55,000 a year and wants to stop full-time work by 50. Her FIRE number at 4% is $1,375,000. With $90,000 in shares and $120,000 in super, the combined pot is only about 15% there. Her real problem is the preservation gap: retiring at 50 means her accessible investments must fund ten years. She re-aimed her $1,400 a month at accessible ETFs and found she can coast comfortably to quit at 53 — three years later, but with the bridge properly funded.
The Nguyens Retire at 45 on Combined Assets
The Nguyen couple, both 45 in Perth, spend $65,000 a year between them and hold $310,000 in shares plus $720,000 in super, contributing $3,000 a month. At a 4% rate their number is $1,625,000. The simulation shows combined assets crossing that inflation-adjusted target in about nine years — age 54. Super unlocks six years before that, so they only need a modest accessible bridge, and they decide to leave work at 48 and draw from shares while super keeps compounding.
Tom Learns His Number Was Too Optimistic
Tom, 38, planned FIRE on a 4.5% withdrawal rate and 8% returns, which put his $90,000-a-year lifestyle 12 years away. Re-running at 3.5% and 6.5% — more realistic for a 45-year retirement and a growth-heavy portfolio — pushed the date to 19 years, which he rejected. The honest fix turned out to be spending: trimming recurring costs by $12,000 a year cut his FIRE number by more than $300,000 and brought the plan back inside 14 years.
Glossary of Terms
- FIRE Number
- The portfolio size required to fund your annual spending at a chosen withdrawal rate — annual spending divided by withdrawal rate.
- Safe Withdrawal Rate
- The annual percentage of a portfolio you can spend in retirement with high confidence the money lasts. Roughly 4% became the classic benchmark for 30-year retirements.
- Preservation Age
- The age at which Australian superannuation can be accessed, subject to a condition of release such as retirement — age 60 for anyone born after 1 July 1964.
Frequently Asked Questions
Everything you need to know about this topic.
Ivy Sinclair-Wren
Financial Chaos Analyst
Ivy Sinclair-Wren is a Financial Chaos Analyst covering investing, AI, wealth psychology, and the emotional consequences of opening finance apps during market crashes. Based in Melbourne, she specializes in demystifying the Australian tax code and helping users navigate the intersection of spreadsheet logic and human irrationality.