FIRE Number Calculator Explained for Australians
Works out how much you need invested to retire early on your current spending. This guide walks through what each input means, the formula behind the answer and a worked example using typical Australian figures. You can follow along in the free FIRE Number Calculator.
Why it matters
Superannuation is Australia’s compulsory retirement savings system. Employers pay the super guarantee into your fund, contributions are taxed concessionally, and the money is generally preserved until you reach preservation age and retire. Small changes to contributions, fees or investment returns compound over decades.
What you need to enter
The calculator asks for 2 inputs. The table shows each one with the example value used later in this guide.
| Input | Example value |
|---|---|
| Annual expenses ($) | 50000 |
| Safe withdrawal rate (%) | 4 |
The formula
FIRE number = annual expenses ÷ withdrawal rate. At 4% that is 25 times your spending.
Worked example
Entering the example values above gives these results:
| Result | Value |
|---|---|
| FIRE number | $1,250,000.00 |
| Monthly spending supported | $4,166.67 |
The headline figure is $1,250,000.00 (FIRE number). Change any input in the calculator and every result updates instantly, so you can test different scenarios side by side.
How the FIRE number changes with annual expenses
The table below keeps every other input at the example value and moves only “Annual expenses ($)” up and down by 10% and 20%. It shows how sensitive the FIRE number is to that one figure.
| Annual expenses ($) | FIRE number |
|---|---|
| 40,000 | $1,000,000.00 |
| 45,000 | $1,125,000.00 |
| 50,000 | $1,250,000.00 |
| 55,000 | $1,375,000.00 |
| 60,000 | $1,500,000.00 |
At 40,000 the result is $1,000,000.00; at 60,000 it is $1,500,000.00. If a small change in this input moves the answer a lot, it is worth double-checking that figure before you rely on the result.
A practical tip
Australians can’t access super before preservation age, so early retirees need enough outside super to bridge the gap.
Keep going
Before relying on the number, read FIRE Number Mistakes Australians Make and How to Avoid Them. You might also find these guides useful:
- How the Super Fees Comparison Calculator Works (With a Worked Example)
- Pension Minimum Drawdown Calculator: Formula, Example and What the Result Means
- Using a Super Guarantee Calculator in Australia: A Step-by-Step Guide
Frequently asked questions
- Are the projections guaranteed?
- No. Investment returns vary from year to year. Treat projections as a guide for planning, not a forecast.
- What is the super guarantee rate?
- It is 12% of ordinary time earnings from 1 July 2025.
- Should I get advice?
- For decisions like salary sacrifice, contribution strategies or retirement income, a licensed financial adviser can look at your full situation. This site provides general information only.
Run your own numbers in the FIRE Number Calculator.
Open the calculatorGeneral information only. Rates and thresholds change, usually on 1 July. Confirm current figures with the ATO or the relevant authority, and get personal advice for decisions about your situation.