What is a FIRE number?

Your FIRE number is the size of portfolio that could cover your spending indefinitely from investment returns, without you having to earn again. It's your annual spending divided by a safe withdrawal rate — so $50,000 a year at a 4% rate is a $1.25 million number.

Is the FIRE number just 25 times my expenses?

25× is the 4% rule in shorthand: spending ÷ 4% is the same as spending × 25. It's a useful starting point, not a law. Choose a 3.5% rate instead and the multiple becomes about 29×; choose 5% and it drops to 20×. The multiple follows whatever withdrawal rate you pick.

Does this calculator account for inflation?

Yes. Everything is in today's money, and the return you enter is a real return — the growth left after inflation. That's why it asks for a 'return above inflation' rather than a headline market return. It's also the main reason two calculators can give very different answers from the same inputs.

What return should I assume?

There's no correct figure, only assumptions you should be able to see and change. Around 5% real is a common assumption for a stock-heavy portfolio over a long horizon, and lower if you hold more bonds or want to be conservative. Lowering it pushes the date out — which is the honest direction to err.

Does the number include taxes and healthcare?

Only if your spending figure does. The calculator takes your annual spending at face value. If your retirement income will be taxed, or your spending doesn't already carry health cover, your real number is higher than the figure shown. See the notes above the questions.

FIRE calculator

How big a portfolio do you need to stop working — and when would you reach it? Enter what you have and what you save. Every assumption is visible, and the number and the date update as you change them.

About 20 more years.

$1,250,000

the portfolio you need to retire on

age 50

when you reach it at $2,500/month

of the way there with what you've saved so far

Keep saving $2,500/month at 5% above inflation and today's $100,000 reaches $1,250,000 around age 50. Change any assumption and watch the date move.

Your age nowInvested todayEverything that's actually invested — not cash, not your house.$Annual spending in retirementIn today's money. This is what sets your number — spend drives everything.$Saving each monthWhat you add to investments monthly, in today's money.$Guaranteed income later, a yearSocial Security or a pension, in today's money. 0 leaves it out. Your own estimate is in your my Social Security account at ssa.gov.$Age it starts67 is the full retirement age for anyone born in 1960 or later (SSA).

Return above inflation5%Real, not nominal. 5% real is a common assumption for a stock-heavy portfolio.Withdrawal rate4%4% is the rule of thumb. It sets your number: at 4% you need 25× your spending, at 3.5% about 29×.

your balance if you keep savingthe number you're aiming at

The link carries your figures, so you can save it or paste it into a thread. Nothing is stored and nothing is sent to us.

Show the year-by-year numbers

Age	Portfolio if you keep saving
30	$100,000
31	$136,500
32	$174,825
33	$215,066
34	$257,320
35	$301,686
36	$348,270
37	$397,183
38	$448,542
39	$502,470
40	$559,093
41	$618,548
42	$680,975
43	$746,524
44	$815,350
45	$887,618
46	$963,498
47	$1,043,173
48	$1,126,832
49	$1,214,674
50	$1,306,907
51	$1,403,753
52	$1,505,440

Three things your number above doesn't tell you

Not reasons to abandon the plan — reasons to know how solid the figure you just got really is. US figures throughout.

3.5%
not 4%
is the rate people set once they've actually arrived.
The withdrawal rate is the input that sets your whole number: at 4% you need 25× your spending, at 3.5% about 29× — a target roughly 15% higher. 4% is the rule of thumb everyone quotes. Among survey respondents who had reached financial independence, the rate they chose for themselves was 3.5%. Move the slider and watch your number move with it.
r/financialindependence 2025 reader survey, n=1,149 (297 reporting FI). Self-selected, self-reported, skewed to high-income US tech workers — not representative. These are rates people target, not what they end up withdrawing.
$15,914
a year, at 60
is health cover the number above probably doesn't include.
Your FIRE number is your spending times a multiple — so it only covers healthcare if your spending figure already does. In the years before Medicare, an unsubsidised benchmark silver plan runs about $15,914 for a 60-year-old just above the subsidy line, of which $10,389 is the increase since the enhanced premium tax credits lapsed. Premiums are age-rated, so a 45-year-old pays less, but these are the expensive years and the ones estimates tend to skip.
KFF. Assumes the enhanced premium tax credits remain lapsed — live legislation. US only. As of July 2026.
What health cover really costs before Medicare →
one number
one smooth line
hides the order your returns arrive in.
The projection uses a single average return every year. Real markets don't work like that, and the sequence matters most right around the finish line — a bad first few years of retirement does far more damage than the same years later. Two people with the same number and the same average can land in very different places. Treat the date above as a reasonable plan, not a guarantee.
This is sequence-of-returns risk, and it's a limit of every average-return calculator, ours included. A constant-return model is a planning tool, not a forecast.

How the FIRE number actually works

It comes down to one sum: the portfolio you need is your yearly spending divided by the rate you plan to draw from it. Everything else is a consequence of those two figures.

Spending sets the size

The single biggest lever isn't your return — it's what a year of your life costs. Trim $5,000 of annual spending at a 4% rate and your number drops by $125,000.

The rate sets the multiple

Divide by 4% and you need 25× your spending. Divide by 3.5% and it's about 29×. The withdrawal rate you're comfortable with decides how many times over you need to cover a year.

Real returns close the gap

The distance between what you have and your number is closed by saving plus growth above inflation. A higher assumed return brings the date closer — which is exactly why the assumption should be visible, not buried.

Common questions about the FIRE number

What is a FIRE number?: Your FIRE number is the size of portfolio that could cover your spending indefinitely from investment returns, without you having to earn again. It's your annual spending divided by a safe withdrawal rate — so $50,000 a year at a 4% rate is a $1.25 million number.
Is the FIRE number just 25 times my expenses?: 25× is the 4% rule in shorthand: spending ÷ 4% is the same as spending × 25. It's a useful starting point, not a law. Choose a 3.5% rate instead and the multiple becomes about 29×; choose 5% and it drops to 20×. The multiple follows whatever withdrawal rate you pick.
Does this calculator account for inflation?: Yes. Everything is in today's money, and the return you enter is a real return — the growth left after inflation. That's why it asks for a 'return above inflation' rather than a headline market return. It's also the main reason two calculators can give very different answers from the same inputs.
What return should I assume?: There's no correct figure, only assumptions you should be able to see and change. Around 5% real is a common assumption for a stock-heavy portfolio over a long horizon, and lower if you hold more bonds or want to be conservative. Lowering it pushes the date out — which is the honest direction to err.
Does the number include taxes and healthcare?: Only if your spending figure does. The calculator takes your annual spending at face value. If your retirement income will be taxed, or your spending doesn't already carry health cover, your real number is higher than the figure shown. See the notes above the questions.