FIRE Calculator

What Is the FIRE Calculator?

FIRE stands for Financial Independence, Retire Early. The idea is simple: if your investments are large enough that you can live on a small, steady share of them each year, you no longer need a job to pay the bills. You can still work if you want to, but work becomes a choice. The amount you need is usually called your FIRE number.

This free FIRE Calculator works out that number from your yearly spending and a withdrawal rate you choose, then projects how your invested savings could grow each year until they reach it. It also shows three useful variations: Lean FIRE for a smaller budget, Fat FIRE for a more comfortable one, and Coast FIRE, the amount you would need invested today to stop saving and still reach your FIRE number by a later age.

What the Calculator Can Do

• FIRE number. The invested amount needed to cover your annual expenses at your chosen withdrawal rate.
• Years and age to financial independence. How many years until your projected portfolio first reaches the FIRE number, and how old you will be.
• Progress today. Your current invested savings as a percentage of the FIRE number, with a progress bar.
• Lean and Fat FIRE. A table compares Lean FIRE (70 percent of your expenses), regular FIRE and Fat FIRE (150 percent of your expenses), with the yearly spending, target and years for each.
• Coast FIRE. Enter a target age, 65 by default, and see how much you need invested today so that growth alone reaches your FIRE number by that age. The tool tells you whether you have already reached it or how much more you need.
• Real return. The calculator turns your expected return and inflation into a real return, so every figure is in today's money.
• Projection chart. Your projected portfolio by age, with lines for the Lean, regular and Fat FIRE targets.
• Year-by-year table. Growth, savings added, portfolio value and progress for each year, with the year you reach FI highlighted.
• Eight currencies. USD, EUR, GBP, INR, BDT, CAD, AUD and JPY. Results are rounded to whole units.

Why the FIRE Number Is Useful

Retirement can feel too far away to plan. A FIRE number turns it into one clear target that is tied to how you actually live. It also shows that spending matters twice: every amount you cut from your yearly budget is money you can save now, and it also lowers the total you need. That is why the FIRE number moves so much when you change annual expenses.

Even if you never plan to retire early, the same numbers help you see how close you are to having real choices, such as working part time, taking a career break or changing to lower-paid work you enjoy more.

How the Calculation Works

The calculator uses a few simple formulas:

• Real return = (1 + expected return) / (1 + inflation) - 1. With a 7 percent return and 3 percent inflation, that is 1.07 / 1.03 - 1, about 3.88 percent. Using the real return keeps every amount in today's money, so a result of 1,000,000 means the buying power of 1,000,000 today.
• FIRE number = annual expenses / withdrawal rate. With 40,000 of expenses and a 4 percent rate, that is 40,000 / 0.04 = 1,000,000.
• Lean FIRE = 0.7 x FIRE number, and Fat FIRE = 1.5 x FIRE number. In the example, 700,000 and 1,500,000.
• Each year, the portfolio grows by the real return and then the yearly saving is added at the end of the year: new balance = old balance x (1 + real return) + yearly saving.
• Years to FI is the first year-end at which the balance is equal to or above the target. If your current savings already reach it, the result is already reached.
• Coast FIRE = FIRE number / (1 + real return) ^ (target age - current age).
• Progress today = current invested savings / FIRE number x 100.

With the example values on the page, someone aged 30 with 50,000 invested who saves 20,000 a year reaches 1,000,000 in 26 years, at age 56. After the first year the balance is about 71,942. Lean FIRE is reached in 21 years, at age 51, and Fat FIRE in 34 years, at age 64. Progress today is 5.0 percent. The Coast FIRE number for age 65 is about 263,555, so this person would need about 213,555 more invested today to stop saving and still reach 1,000,000 by 65.

The projection runs for up to 80 years. If the target is not reached in that time, the tool says so instead of showing a number. All calculations run in your browser; nothing is sent to a server.

About the Withdrawal Rate

The withdrawal rate is the share of your portfolio you plan to take out in the first year of retirement. A 4 percent rate is a popular starting point in FIRE planning and is the default here, but it is a rule of thumb, not a promise. A lower rate, such as 3 or 3.5 percent, gives a larger FIRE number and more room for bad market years, which many people prefer when retirement could last 40 or 50 years. A higher rate gives a smaller number but a higher risk of running short. Try a few rates to see how much the target changes.

How to Use the Calculator

1. Choose the Currency you want amounts shown in.
2. Enter your Current Age and your Annual Expenses: what you expect to spend each year once you stop working, in today's money.
3. Enter your Invested Savings Now. Count investments meant for the long term, not your emergency fund or the equity in the home you live in.
4. Enter how much you add to investments each year in Saved Per Year.
5. Set an Expected Return and Inflation. Both are yearly averages.
6. Set your Withdrawal Rate, 4 percent by default, and a Coast Target Age, 65 by default.
7. Read your years to FI and age at FI, the progress bar, the FIRE number, real return and Coast FIRE cards, the FIRE levels table and the chart. Scroll down for the year-by-year projection.
8. Use Reset to example to return to the starting values.

Practical Ways to Use It

• Test a raise in savings. See how many years you gain by saving an extra 5,000 a year.
• Test a lower budget. Cut annual expenses by 10 percent and watch both the target and the timeline move.
• Check Coast FIRE. If you are close to your Coast number, you may be able to save less later and let growth do the rest.
• Stress test your plan. Try a lower return, higher inflation or a 3.5 percent withdrawal rate to see a more cautious result.
• Track progress yearly. Update your invested savings once a year and check that your progress percentage is rising.

Limitations

The calculator uses the same return every year. Real markets rise and fall, and the order of good and bad years matters a lot when you start withdrawing money. Two people with the same average return can end up in very different places. Treat the result as a planning estimate, not a forecast.

Taxes, fund fees, pensions, government benefits, inheritances and one-off costs are not included. Your yearly saving is assumed to stay the same in today's money until you reach FI, and it is added once at the end of each year. Spending after retirement is assumed to be flat. Health care, children and housing costs can change a lot over a long retirement. Years are counted in whole years, so the real date could be a few months earlier.

What to Do and What Not to Do

Do base annual expenses on real spending records, not a guess. Do use cautious returns and include inflation, because a plan that only works with high returns is fragile. Do keep an emergency fund outside your FIRE investments. Do revisit your plan every year as your life changes.

Do not count the home you live in as part of your invested savings, because it does not pay you an income unless you sell it. Do not treat the 4 percent rate as guaranteed. Do not quit your job based on one calculator result. This tool is for education and planning, not financial advice; for a big decision, speak to a qualified financial adviser.

Frequently Asked Questions