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FI Number Calculator

Your FI number is the portfolio that covers your spending without a paycheck. Enter what you spend in a year and see it.

Your numbers

$

What you expect to spend in a year once you stop working, in today's dollars.

2.5%6.0%

The share of the portfolio you draw in year one. 4% is the common starting point, and it is genuinely debated.

$

Invested assets only: brokerage, retirement accounts, and cash you count as part of the portfolio. Add it to see your progress.

Your FI number

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How much the withdrawal rate matters

The same spending, priced at five different withdrawal rates.

Your FI number at other withdrawal rates

There is no settled answer on the right rate, and the number moves a lot. Moving from 5% to 3% takes the target from 20 times your annual spending to more than 33 times it.

Withdrawal rate FI number Multiple of spending

Stop re-typing your numbers

This page is a snapshot from figures you keyed in by hand. Ember keeps the same numbers current on their own: every account in one ledger, real net worth, and spending you can actually trust.

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Ember is in private beta and invite-only right now.

This tool provides estimates for general planning purposes only, not personalized financial or tax advice. It relies on simplifying assumptions (see "How this is calculated" below) that will not match your actual results. Consult a qualified professional before making financial decisions.

How this is calculated

The formula

FI number = annual expenses ÷ (safe withdrawal rate ÷ 100)

At a 4% withdrawal rate that is simply 25 times your annual spending; at 3% it is about 33 times, and at 5% it is 20 times. If you entered your current invested net worth, progress is that balance divided by the FI number, capped at 100%.

What a "safe withdrawal rate" means

It is the percentage of the portfolio you withdraw in the first year, with later withdrawals rising to keep pace with inflation. The widely quoted 4% figure comes from studies of how portfolios would have fared across historical 30-year periods. It is a rule of thumb, not a guarantee, and reasonable people argue for anything from 3% to 5%. The safe withdrawal rate explorer shows what the historical record actually says.

What this does not account for

  • Anything other than the portfolio. Social Security, a pension, rental income, or part-time work all reduce what the portfolio has to cover. The Barista FIRE calculator handles the part-time case.
  • Spending that changes. One flat annual figure carries from the first year to the last. Real spending moves with health, housing, and family.
  • Taxes. Withdrawals from traditional accounts are taxable income. If your spending figure is what you need after tax, the portfolio has to be larger.
  • How long the money must last. A withdrawal rate that works over 30 years is a different proposition over 50.

Shared assumptions

  • Returns are real, not nominal. Every return figure on this page is already inflation-adjusted, so all dollar amounts are in today's money. There is no separate inflation input to set.
  • Returns are smooth. The same return is applied every year. Real markets are not smooth, and the order in which good and bad years arrive changes outcomes materially.
  • No taxes, fees, or lumpy spending. Investment fees, taxes on withdrawals, one-off costs, and changes in your spending over time are not modelled.
  • Nothing leaves your browser. The whole calculation runs client-side. We do not receive, log, or store anything you type.