The FIRE number and the FI number are the same target: annual spending divided by your withdrawal rate. At $45,000 of spending and 4%, that is $1,125,000; at 4.5% it is $1,000,000. People use both names for one figure, with FIRE usually naming the movement and the lifestyle, and FI naming the state of independence. This calculator works out the number itself, then shows how contributions and time change when you reach it.
Spending $40,000 a year at a 4% withdrawal rate needs $1,000,000 invested. The Coast FIRE number for age 30 is $181,290, so you still need $181,290.
Spending $40,000 a year at a 4% withdrawal rate needs $1,000,000 invested. Your Coast FIRE number for age 30 is $181,290, and your portfolio is already $0 past it.
The letters FI stand for financial independence and RE for retire early, so FIRE is the pair together. Somewhere along the way the target picked up two labels, and the internet now uses them almost interchangeably. A FIRE number is what you need to retire early. An FI number is what you need to stop depending on a job. If you plan to keep working in some form after the number, the distinction is real; if you plan to stop, they collapse into one figure. This page calculates the value and uses both names, because spending divided by withdrawal rate does not care which word you prefer.
The shortcut is one division. A 4% withdrawal rate means taking one twenty-fifth of the portfolio each year, so the portfolio has to be twenty-five times the annual withdrawal. That is where 25x comes from, and why the figure is easy to check by hand: multiply your spending by twenty-five and you have the answer. The shortcut carries an assumption with it, namely that 4% lasts through a retirement of unknown length. Change the rate and the multiple changes with it: 3.5% is about 28.6x, 5% is 20x. The multiplication is trivial; choosing the multiple is the actual work.
A FIRE number is a clean figure with messy assumptions behind it. It assumes spending stays flat in real terms, that the portfolio earns a steady real return, and that taxes, health cover and one-off costs already sit inside the spending figure. It also assumes an average sequence of returns, which nobody experiences. Retiring into a long decline is not the same as retiring into a boom, even with identical averages, which is why the number is a starting line rather than a guarantee. Treat it as a target you recalculate, not a verdict you reach once.
Yes. Both are annual spending divided by a withdrawal rate. FIRE number is the usual term in the early retirement community, while FI number is used when the goal is independence from paid work rather than retirement itself. The arithmetic is identical.
Because 25 is one divided by 0.04. A 4% withdrawal rate takes four cents from every dollar of portfolio each year, so a portfolio of 25 times your spending produces the same amount. At 3.5% the multiple is about 28.6, and at 5% it is 20.
Yes, but inside the spending figure. Model the after-tax spending you need and check the effective rate you will pay on withdrawals. Portfolio income is taxed differently depending on the account and where you live, so adding a flat percentage on top of a pre-tax number is usually less accurate than building the tax into the budget.
Usually yes. A longer retirement has more room for a bad sequence of returns, and health cover often costs more before state benefits begin. Many planners use 3% to 3.5% for retirements starting in the 40s, which raises the multiple to between about 28.6 and 33 times spending.
Once a year is enough for most people, plus after any large change: a new job, a house, a child, or a market fall serious enough to make the news. Recalculating every month mostly measures your mood rather than your plan.