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Financial Independence Retire Early (FIRE) Calculator with Inflation Adjustment

FIRE arithmetic is deceptively simple: your target corpus is annual spending divided by your safe withdrawal rate, so a 4% rate means 25 times expenses. What actually determines the date is your savings rate — the share of take-home pay you invest — because it simultaneously raises contributions and lowers the number you need.

FIRE number
$1,125,000
25.0× annual expenses
FIRE age
47.9
15.9 years from now
Coast FIRE today
$120,639
Enough to coast to 65 with zero new savings
Savings rate
37.0%
Of savings + spending

At a 4% withdrawal rate you can safely draw $45,000 a year from $1,125,000.

Ten-year compound growth path
YearProjected portfolioFIRE targetProgress
Age 33$155,939$1,125,00014%
Age 34$194,475$1,125,00017%
Age 35$235,797$1,125,00021%
Age 36$280,107$1,125,00025%
Age 37$327,619$1,125,00029%
Age 38$378,567$1,125,00034%
Age 39$433,197$1,125,00039%
Age 40$491,777$1,125,00044%
Age 41$554,591$1,125,00049%
Age 42$621,946$1,125,00055%

The 4% rule and where it came from

The Trinity Study tested historical US portfolios of stocks and bonds over rolling 30-year windows and found that withdrawing 4% of the initial balance, inflation-adjusted, survived almost every period. Longer retirements of 40-50 years, which early retirees face, are usually modelled at 3.25-3.5% instead.

Coast FIRE explained

Coast FIRE is the balance at which compound growth alone reaches your target by traditional retirement age. Once you hit it you can stop contributing entirely and simply cover living costs with any job. The card above discounts your FIRE number back to today at your expected return over the years remaining until 65.

Sequence of returns risk

Two retirees with identical average returns can end up in completely different places if one meets a bear market in the first three years. Mitigations include a two-year cash buffer, a rising equity glidepath, and flexible spending rules that trim withdrawals by 10% after a down year.

The four types of FIRE

TypeExpense multiplierTypical corpus (on $45k spend)Withdrawal marginBest suited to
Lean FIRE0.75×$843,750Tight — needs flexibilityLow cost-of-living, minimalists
Barista FIRE0.6× + part-time income$675,000Wide — wages cover gapsThose wanting health cover
Coast FIREFront-loadedVaries by ageN/A until traditional ageYoung high earners
Standard FIRE1.0×$1,125,000Trinity-tested 4%Most FIRE followers
Fat FIRE1.25-1.5×$1.4m-$1.7mVery wideHigh earners, families

People also ask

What is the 4% safe withdrawal rate rule?

Derived from the Trinity Study, it states that withdrawing 4% of your initial portfolio annually, adjusted for inflation, had a very low probability of depletion over a 30-year retirement. Early retirees often use 3.25-3.5% for longer horizons.

How does Coast FIRE differ from traditional FIRE?

Coast FIRE means you have already invested enough that compound growth alone will reach your retirement target by traditional retirement age, even if you never contribute another dollar.

Does the FIRE number account for inflation?

Yes, when you enter a real (post-inflation) return such as 7% rather than a nominal 10%. All balances then represent today's purchasing power.

Three worked examples

Same engine, three different starting points — useful if you want to see how sensitive the answer is before you type your own numbers in.

Example 1: current age 24.96 years, currency "USD $"

FIRE number
$1,125,000
25.0× annual expenses
FIRE age
40.9
15.9 years from now
Coast FIRE today
$74,925
Enough to coast to 65 with zero new savings
Savings rate
37.0%
Of savings + spending

On the lower / more conservative end. At a 4% withdrawal rate you can safely draw $45,000 a year from $1,125,000.

Example 2: current age 32 years, currency "USD $"

FIRE number
$1,125,000
25.0× annual expenses
FIRE age
47.9
15.9 years from now
Coast FIRE today
$120,639
Enough to coast to 65 with zero new savings
Savings rate
37.0%
Of savings + spending

A typical middle-of-the-road setup. At a 4% withdrawal rate you can safely draw $45,000 a year from $1,125,000.

Example 3: current age 41.6 years, currency "GBP £"

FIRE number
£1,125,000
25.0× annual expenses
FIRE age
57.5
15.9 years from now
Coast FIRE today
£230,979
Enough to coast to 65 with zero new savings
Savings rate
37.0%
Of savings + spending

On the higher / more demanding end. At a 4% withdrawal rate you can safely draw £45,000 a year from £1,125,000.

Quick answers about the FIRE (Retire Early) Calculator

What exactly does the FIRE (Retire Early) Calculator work out?

FIRE arithmetic is deceptively simple: your target corpus is annual spending divided by your safe withdrawal rate, so a 4% rate means 25 times expenses. You enter currency, current age, annual expenses and current invested net worth (plus 4 more optional details) and the result panel updates straight away, so you can compare two or three versions of the same question in a few seconds.

What do I need before I start?

Only 8 fields: currency, current age, annual expenses, current invested net worth, monthly savings, expected real return, safe withdrawal rate and fIRE type. Nothing else is needed and nothing is stored.

How is it calculated — the 4% rule and where it came from?

The Trinity Study tested historical US portfolios of stocks and bonds over rolling 30-year windows and found that withdrawing 4% of the initial balance, inflation-adjusted, survived almost every period. The same maths runs inside this page, so hand-checking the result on paper gives you the identical figure.

Why do two calculators give me different answers for fIRE (Retire Early)?

Coast FIRE is the balance at which compound growth alone reaches your target by traditional retirement age. Different sites pick different assumptions, so always check which method a calculator states before you trust the gap between two numbers.

What does the "The four types of FIRE" table on this page tell me?

It is the reference range this tool works against — 5 rows from "Lean FIRE" (0.75×) up to "Fat FIRE" (1.25-1.5×). Use it to sanity-check whether the number you just calculated sits where you expected it to.

Which currency should I pick?

The dropdown offers 5 choices — USD $, GBP £, EUR €, CAD C$ and AUD A$. Pick the one that matches your real situation rather than the one you would like to be true; currency usually moves the final figure more than any other single input, so it is worth running it twice with the option above and below your guess.

Does it work in both metric and imperial (or another currency)?

Yes. The "Currency" control converts every field and every result, so you never have to convert anything by hand before typing it in. Switch it after entering your numbers and the output re-renders instantly in the new system.

Do I have to press a button or reload the page to see the result?

No. FIRE (Retire Early) Calculator runs completely inside your browser, so the moment you change a value the cards recalculate — there is no submit step, no page reload and no waiting for a server round trip. That also means it keeps working on a weak or intermittent mobile connection.

Is it free, and do you keep what I type?

It is free with no sign-up, no app install and no usage limit. Nothing you enter into FIRE (Retire Early) Calculator leaves your device — the calculation is JavaScript running locally, so there is no upload of your figures to DrHint or anyone else.

Can I use it on a phone?

Yes — the layout stacks to a single column on small screens and the number fields open the numeric keypad on both Android and iOS. Many people bookmark this page or add it to their home screen and re-open it whenever the question comes up.

Anything to be careful about with the result?

Derived from the Trinity Study, it states that withdrawing 4% of your initial portfolio annually, adjusted for inflation, had a very low probability of depletion over a 30-year retirement. Treat the output as a well-grounded estimate for planning, not as a professional, legal or medical decision on its own.

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