Type what you take home, what you spend and what you have saved. See your FIRE number, the age your savings reach it, and the earliest age your money lasts in 8 of 10 market paths. Lean FIRE, fat FIRE and coast FIRE included. Any country, any currency.
Worked out in this browser. Nothing is sent anywhere unless you press the AI button.
State pension, Social Security, a work pension. Leave it at 0 if you have none.
Four numbers give the first answer; everything else is optional and moves the answer when you add it.
The rules are all here, in plain words. Nothing is hidden and nothing is rounded up to sound better.
| Number | How it is worked out |
|---|---|
| FIRE number | Your yearly spending once you stop work, divided by your withdrawal rate. At 4% that is 25 times the spending. As in the rule, it leaves out pensions; the full plan counts them. |
| Lean FIRE | The same rule on your must-spend part only: rent, food, bills. It starts at 75% of your spending; change it on the Spending page. |
| Fat FIRE | The same rule on one and a half times your spending. There is no fixed line between regular and fat FIRE; this is our example of a more generous life. |
| FIRE age | The first age your savings reach the FIRE number if you keep working and saving as now, with typical returns every year (for shares, the middle year of the US record 1928–2025, about 6.9% above inflation). |
| Stop work at | The earliest age at which your whole plan lasts to the end (90 unless you change it) in 8 of 10 of 1,000 random market paths, with tax on withdrawals and anything else you add. |
| Coast FIRE | What you need invested today so that, with nothing more added, it grows to your FIRE number by the usual pension age for your currency: 67 in the US and the UK, 58 for the EPS pension in India, 60 for the SSS pension in the Philippines. The coast age is when your own savings get there. |
Market numbers: US yearly returns 1928–2025 from Aswath Damodaran, NYU Stern (updated 5 January 2026). Press Cautious on the Market page to plan with 5.0% for shares instead. The 4% rule: Bengen, Journal of Financial Planning, October 1994.
Two made-up people, run through the calculator as it is today. Press “See a sample plan” above to open the one in your currency and check every number.
| Maya, 30, in dollars | Rohan, 28, in rupees | |
|---|---|---|
| Takes home a month | $6,000 | ₹1,20,000 |
| Spends a month | $3,500 | ₹60,000 |
| Saved and invested (in shares) | $50,000 (90%) | ₹8,00,000 (90%) |
| Saves of their pay | 42% | 50% |
| FIRE number (25 times a year of spending) | $1,050,000 | ₹1,80,00,000 |
| Lean FIRE and fat FIRE | $787,500 and $1,575,000 | ₹1,35,00,000 and ₹2,70,00,000 |
| Savings reach the FIRE number (typical returns) | at 48, in 18 years | at 43, in 15 years |
| Can stop work (money lasts to 90 in 8 of 10 market paths) | at 49 | at 43 |
| Coast FIRE: invested today to coast to the pension age | $106,747 by 67; reached at 33 | ₹28,20,150 by 58; reached at 32 |
Both save over a third of their pay, so both reach the FIRE number before 50. The 1,000-path test agrees within a year or two: the rule and the full plan are close when nothing is locked away and no pension is counted. Add a pension and the age comes down; add a home deposit and it goes up.
The savings you need to stop working for good: your yearly spending divided by a safe withdrawal rate. At 4% that is 25 times what you spend in a year, so spending 40,000 a year needs 1,000,000 in any currency. This calculator shows it as soon as you type your spending, with lean and fat FIRE next to it.
Add up a year of spending once you stop work: home, food, health cover, travel, help for family. Divide it by your withdrawal rate: by 0.04 at 4% (the same as times 25), by 0.035 at 3.5% (about 28.6 times). The plain rule leaves out any pension; the full plan counts it year by year and needs less when a pension comes in.
The point where what you have invested will grow to your FIRE number by the usual pension age without adding anything more. From then on your pay only has to cover your costs, so a lower-paid or part-time job is enough. The calculator shows the amount you need invested today to coast, and the age your savings reach it.
Lean FIRE means stopping work on a bare budget, fat FIRE on a generous one; neither has a fixed number. Here lean FIRE covers only your must-spend part (75% of your spending unless you change it on the Spending page) and fat FIRE one and a half times your spending, each divided by the same withdrawal rate.
The 4% rule comes from Bengen's 1994 study of 30-year retirements in US markets, and Morningstar's 2026 research put a safe starting rate at 3.9% for 30 years. Stopping work at 40 can mean 50 years of withdrawals, so a lower rate is safer. Rather than trust one rule, this calculator tests your whole plan to the age you choose on 1,000 market paths and gives the earliest age that lasts in 8 of 10.
Start from your FIRE number, then allow for what the rule skips: more years to pay for, tax on withdrawals, and savings you cannot touch before a set age (a 401(k) before 59½, EPF before 58). The plan's “How much you need” card works this out for your stop-work age, counting locked accounts, tax and pensions.
The higher the share of your pay you save, the sooner you get there, because each amount you do not spend is also an amount you will not need later. Type your own pay and spending: the calculator shows your savings rate and the age it gives. Try a few spending levels and watch how many years each change moves.
Yes. Pick your currency. Market returns are set above inflation, so they work with any country's prices, and the helpers add common accounts and pensions for India (EPF, PPF, NPS), the US (401(k), IRA, Social Security), the UK (workplace pension, ISA, State Pension), the Philippines and Nigeria.
The plan is worked out in your browser and kept in this browser, with a delete button, or in a file you download. Only the Explain my plan button sends the plan's numbers, without names, and the page says so next to it. What you send to the AI is saved to ClapAssist so our tools can fill it in for you next time; see or delete it at clapassist.com/my-data/.
Yes, with no account and no limit: the FIRE number, the ages, the charts, the scenarios and the downloads are free. Only the optional AI explanation has a small free daily allowance.
ClapAssist is a Mac and Windows app that listens to your interview call and shows you what to say, including when they ask about pay. It stays out of screen share on every plan; only you can see it.
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