Financial independence · retire early

The free FIRE calculator that models real life.

How much do you need to retire — and when can you stop working? This FIRE calculator covers Coast, Lean and Fat FIRE, works for couples, and factors in pensions and Social Security. Fill in a few numbers below and find out in seconds. Free, private, no sign-up.

How much do you need to retire?

Fine-tune (optional)
Your FIRE number
$1.3M$1,250,000

That's about what you'd need invested to retire at 55 and spend $50,000 a year — roughly 25× your yearly spending.

93% chance it lasts
how often a 4% withdrawal rate survived every retirement since 1871
Could retire by age 55
earliest age your savings reach your FIRE number
Other styles of FIRE
Lean FIRE
$1M
a bare-bones budget
Coast FIRE
$369.1k
save this, then coast
Fat FIRE
$2.5M
a generous lifestyle
Optional · go deeper

Want a more realistic plan for free?

Real life isn't one flat number. Add a spouse who keeps working, a mortgage that ends, health insurance before Medicare, a pension, and Social Security — then see how your plan holds up across 150+ years of markets.

About this calculator

A free FIRE calculator for every kind of FIRE

A FIRE calculator answers two questions: how much do you need to retire, and when can you stop working? This one is built to be the best FIRE calculator for plans that reflect real life — not a back-of-the-napkin estimate. On the surface it's a simple FIRE calculator: enter your age, savings, and yearly spending to see your number in seconds. Underneath sits a full multi-phase planner for when you want the detail, and everything runs in your browser with no sign-up.

Every kind of FIRE, one tool

Financial independence isn't one-size-fits-all, so adjust your spending and the same tool covers each route to it:

Coast FIRE
As a Coast FIRE calculator it finds the point where your savings will compound into a full nest egg on their own — so you can stop contributing and just cover today's costs.
Lean FIRE
Run it as a Lean FIRE calculator built around a frugal budget — roughly 20× your annual spending.
Fat FIRE
Or a Fat FIRE calculator for a more generous lifestyle of around 50×, with the classic 4% rule (about 25×) sitting in between.

Whichever target you pick, you instantly see the portfolio it requires today — which makes it easy to weigh your options side by side.

Built for couples, with Social Security

Most tools break the moment two people share a plan, so this was designed as a FIRE calculator for couples from day one. Give each partner their own savings rate, retirement age, pension, and Social Security start date — the common case where one person retires early while the other keeps working is exactly what a good Coast FIRE calculator for couples should handle.

It's also a Coast FIRE calculator with Social Security: future benefits are folded into how much you still need to save, so the number you coast to reflects your actual household — not a generic rule of thumb.

A retirement plan, tested against history

The plan doesn't end the day you quit. As a true retirement FIRE calculator, it follows your money all the way through drawdown — a mortgage that gets paid off, a health-insurance bridge before Medicare, and income that arrives in waves at different ages.

Every change you make is replayed through more than 150 years of real market history — from the Great Depression to 2008 and 2022 — and through thousands of Monte Carlo sequences drawn from that same data. You get a clear success rate, a range of outcomes, and the earliest age you could safely retire, all in today's dollars and grounded in the standard 4% safe-withdrawal benchmark.

Start in seconds — free and private

Whether you came looking for a cost FIRE calculator, the best Coast FIRE calculator, or simply a clear FIRE calculator for retirement, you can start right above. Enter your age, savings, and spending, read your FIRE number, then open the detailed planner to match it to your real life. When the plan looks right, hit Share — your scenario is saved into a private link that only you control, so you can revisit it later or send it to your partner without ever creating an account.

Frequently asked questions

What is a Coast FIRE calculator?+

A Coast FIRE calculator works out the moment you've saved enough that your investments will grow into a full retirement nest egg on their own, without you adding another dollar. Once you hit that 'coast' number, you only need to earn enough to cover your current expenses while compounding finishes the job. This calculator finds that crossover point for you and factors in pensions and Social Security, so the number reflects your real situation rather than a simple multiplier.

What is a FIRE calculator?+

A FIRE calculator estimates how much money you need to retire early and when you can stop working. You enter your age, current savings, how much you invest each year, and your expected retirement spending, and it returns your FIRE number — the portfolio that funds your lifestyle — along with the age you can reach it. This FIRE calculator goes further than a simple multiplier by backtesting that plan against real market history and Monte Carlo scenarios.

When can I retire according to a FIRE calculator?+

Enter your age, current savings, yearly contributions, and target retirement spending, and the FIRE calculator projects the earliest age your portfolio can support you for life. It grows your savings at an expected real return until they reach your FIRE number, then tests that retirement date across 150+ years of market history — so you see how safe the date really is, not just the average case.

How do I calculate my FIRE number?+

Divide your expected annual retirement spending by your safe withdrawal rate. At the classic 4% rate that means multiplying your yearly spending by 25 — so $40,000 a year needs roughly $1,000,000. For a leaner plan use about 20× spending, and for a more generous Fat FIRE lifestyle around 50×. Enter your spending in the calculator above and it works out the number instantly, then shows how long it is likely to last.

Which calculator should I use for early retirement (FIRE)?+

Use a FIRE calculator that models your actual plan instead of a single flat number — ideally one that handles saving and drawdown together, supports couples and Social Security, and backtests against real market history rather than assuming a fixed return. This free calculator does all of that, which makes it a strong choice for planning early retirement.

What is the 4% rule for FIRE?+

The 4% rule is a guideline that says you can withdraw about 4% of your starting portfolio in your first year of retirement, then adjust that dollar amount for inflation each year, with a strong chance your money lasts 30 or more years. It's where the '25× your annual spending' FIRE number comes from (100% ÷ 4% = 25). This calculator lets you change the withdrawal rate and then stress-tests it against real market history.

What does FIRE stand for in a FIRE calculator?+

FIRE stands for Financial Independence, Retire Early. A FIRE calculator helps you find the point of financial independence — a portfolio large enough that investment returns can cover your living costs — so that paid work becomes optional and you can retire earlier than the traditional retirement age.