FIRE Number Calculator
FIRE NumberFind how much you need to retire (your FIRE number) using a sustainable withdrawal rate—e.g. the 4% rule. Enter annual expenses and withdrawal rate to get the portfolio size that would support that spending. Add savings and contributions to see years until you reach it and growth over time.
Spending per year in retirement (today's dollars)
e.g. 4% rule
Annual amount that reduces portfolio need
When set, we use inflation-adjusted (real) returns so the projection stays in today's dollars.
Fixed date for your plan
e.g. 4% rule sets target
For savings rate
Savings rate: 24% of income
Uses the inflation rate above; contributions grow each year to keep real purchasing power.
Today's dollars adjust for inflation so the number stays meaningful.
Portfolio to support $50,000/year at 4% withdrawal
Chart shows accumulation phase only (up to retirement).
Many early-retirement benchmarks cite 50%+ savings rate
Your spending in retirement: $50,000/year (today's dollars).
What if I saved more?
At $3,000/mo → $1,793,128 at age 65 (on track)
See every year until you reach your FIRE number (table below)
Not financial advice. By using this calculator you agree to our Terms.
Your plan
$2,000/month until age 65
$1,284,280 at age 65
On track for your FIRE number
Save $1K more/month
$3,000/month until age 65
$1,793,128 at age 65
On track
| Year | Start Balance | Contribution | Growth | End Balance |
|---|---|---|---|---|
| Start | $100,000 | $0 | $0 | $100,000 |
| 1 | $100,000 | $24,000 | $4,437 | $128,437 |
| 2 | $128,437 | $24,000 | $5,574 | $158,011 |
| 3 | $158,011 | $24,000 | $6,757 | $188,769 |
| 4 | $188,769 | $24,000 | $7,988 | $220,756 |
| 5 | $220,756 | $24,000 | $9,267 | $254,023 |
| 6 | $254,023 | $24,000 | $10,598 | $288,621 |
| 7 | $288,621 | $24,000 | $11,982 | $324,603 |
| 8 | $324,603 | $24,000 | $13,421 | $362,024 |
| 9 | $362,024 | $24,000 | $14,918 | $400,942 |
| 10 | $400,942 | $24,000 | $16,475 | $441,416 |
| 11 | $441,416 | $24,000 | $18,094 | $483,510 |
| 12 | $483,510 | $24,000 | $19,777 | $527,287 |
| 13 | $527,287 | $24,000 | $21,528 | $572,815 |
| 14 | $572,815 | $24,000 | $23,350 | $620,165 |
| 15 | $620,165 | $24,000 | $25,243 | $669,408 |
| 16 | $669,408 | $24,000 | $27,213 | $720,622 |
| 17 | $720,622 | $24,000 | $29,262 | $773,883 |
| 18 | $773,883 | $24,000 | $31,392 | $829,276 |
| 19 | $829,276 | $24,000 | $33,608 | $886,884 |
| 20 | $886,884 | $24,000 | $35,912 | $946,796 |
| 21 | $946,796 | $24,000 | $38,309 | $1,009,104 |
| 22 | $1,009,104 | $24,000 | $40,801 | $1,073,906 |
| 23 | $1,073,906 | $24,000 | $43,393 | $1,141,299 |
| 24 | $1,141,299 | $24,000 | $46,089 | $1,211,387 |
| 25 | $1,211,387 | $24,000 | $48,892 | $1,284,280 |
For illustration only. The 4% rule is a heuristic; outcomes depend on sequence of returns and inflation. This is not financial advice.
About this calculator
The FIRE number is the portfolio size that would support your annual spending at a chosen withdrawal rate (e.g. 4% per year). This calculator is for anyone pursuing financial independence or early retirement and wants a target number and a timeline to reach it.
Use it to set a savings target and to see how current savings plus contributions, growing at an expected return, project to that target. The 4% rule is a common heuristic from retirement research; your own rate may vary with risk tolerance and planning horizon. Results are for illustration only.
How this is calculated
FIRE number
Your FIRE number is the portfolio size that, at your chosen withdrawal rate, would pay your annual expenses (minus any pension or Social Security). Formula:
FIRE number = (Annual expenses − Pension/SS offset) ÷ Withdrawal rate
Example: $50,000/year at 4% → $50,000 ÷ 0.04 = $1,250,000. With a $20K pension offset, you need ($50,000 − $20,000) ÷ 0.04 = $750,000. The "4% rule" is often cited from the Trinity study. We also show the nominal amount needed at retirement if expenses grow with inflation.
Years to FIRE
We project your current savings plus monthly contributions growing at the expected return until the balance reaches your FIRE number. The same compound growth logic as the Investment Calculator (solve for years): each year, growth is applied to the balance and then contributions are added.
Inflation and purchasing power
The main FIRE number is in today's dollars. If you enter an inflation rate, we show the nominal portfolio you'd need at retirement (when your spending has grown with inflation) and what your annual spending in today's dollars would equal in nominal dollars at that time.
Assumptions
We assume constant return and level contributions. The 4% rule is based on historical data; future results may differ. Sequence of returns and inflation can affect outcomes. Results are for illustration only.
Ready to run Monte Carlo and 20+ scenarios with your real numbers?
Get started free