---
title: "FIRE Number Calculator: 25× Spending Explained | Bond Meadow"
description: "Work out your FIRE number: yearly spending divided by a withdrawal rate you choose (25 times at 4%), with your progress and other rates compared."
url: https://bondmeadow.bond/fire-number-calculator/
---

Financial independence

# FIRE number calculator

The FIRE number is the size of portfolio people in the financial independence movement aim for before work becomes optional: yearly spending divided by the share they plan to withdraw each year.

## The outlook

Your FIRE number is **$1,000,000**: 25 times yearly spending of $40,000, at a 4% withdrawal rate.

Saved so far: $150,000 15% of the way

$850,000 to go.

| Rate | Multiple | FIRE number | Comparison bar |
| --- | --- | --- | --- |
| 3% | 33.3× | $1,333,333 |  |
| 3.5% | 28.6× | $1,142,857 |  |
| 4% (yours) | 25× | $1,000,000 |  |
| 4.5% | 22.2× | $888,889 |  |
| 5% | 20× | $800,000 |  |

## Where the multiple comes from

FIRE number = yearly spending ÷ withdrawal rate

At a 4% withdrawal rate that is 1 ÷ 0.04 = 25 times your yearly spending; at 3.5% it is about 28.6 times, at 5% it is 20 times. Count the spending you expect in retirement, after any pension or other income you are confident of: only the gap has to come from savings.

The 4% figure traces back to William Bengen's 1994 study of US stock and bond returns since 1926. He found that a first-year withdrawal of 4% of the portfolio, raised each year with inflation, had never exhausted a portfolio in under 33 years in the periods he tested, while 4.25% could run out in 28. The 1998 Trinity study by Cooley, Hubbard and Walz ran similar tests on stock and bond returns from 1926 to 1995, for payouts lasting 15 to 30 years.

Those are findings about the past, for particular portfolios and retirement lengths, before taxes and fees. They do not make 4%, or any rate on this page, safe for you. Early retirees may need their money to last 40 or 50 years, and the [withdrawal rate explorer](https://bondmeadow.bond/safe-withdrawal-rate/) shows how much that and the order of returns matter. The ladder under the result lets you see the same spending at several rates.

## Sources

1. William P. Bengen, [“Determining Withdrawal Rates Using Historical Data”](https://www.financialplanningassociation.org/sites/default/files/2021-04/MAR04%20Determining%20Withdrawal%20Rates%20Using%20Historical%20Data.pdf), *Journal of Financial Planning*, October 1994 (reprinted by the Financial Planning Association, 2004).
2. Philip L. Cooley, Carl M. Hubbard and Daniel T. Walz, [“Retirement Savings: Choosing a Withdrawal Rate That Is Sustainable”](https://www.aaii.com/journal/article/retirement-savings-choosing-a-withdrawal-rate-that-is-sustainable), *AAII Journal*, February 1998 (the “Trinity study”).

## Questions

**Should I use today's spending or retirement spending?**

Retirement spending, in today's money. Some costs fall, such as commuting or a paid-off mortgage; others can rise, such as health care or travel. Pension or other guaranteed income lowers the amount the portfolio has to provide.

**Is 25 times my spending enough?**

Nobody can promise that. It is what a 4% withdrawal rate implies, and that rate comes from historical studies, not a guarantee. A lower rate gives a bigger target and more room for bad markets, a longer retirement or higher costs.

**Does the FIRE number include my home?**

Usually not. The number is the invested money that pays for spending, so a home you live in is left out unless you plan to sell it or rent part of it out.