FIRE Calculator
Free FIRE calculator with the 4% rule, savings rate, and years to financial independence. Plan in USD. No signup, private.
Last updated 2026-05-28 · Davi Baptista
Read also: FIRE Movement Guide, Juros compostos explicados, Calculadora de aposentadoria
How it works
FIRE (Financial Independence, Retire Early) means building a portfolio large enough that a safe withdrawal rate covers living expenses—this FIRE calculator estimates your target and years to reach it.
FIRE means your investments can cover living costs without a paycheck. Your FIRE number ≈ 25× annual spending (4% withdrawal). Example: $40,000/year expenses → about $1M target. A 50% savings rate can reach FIRE in roughly 17 years at ~7% returns — this calculator shows your timeline from income, spending, and current assets.
FIRE number, savings rate, and withdrawal math
Financial Independence, Retire Early (FIRE) usually starts with annual spending multiplied by 25—the classic 4% rule—or a safer 3–3.5% withdrawal rate if you retire early with a long horizon.
Savings rate dominates time-to-FIRE more than chasing extra return. Cutting fixed costs or raising income moves the date faster than picking a hotter fund.
Model healthcare before Medicare, sequence-of-returns risk in the first five years of withdrawals, and partial work or side income if you coast-FIRE.
Use compound interest for accumulation, retirement calculator for Social Security and pension offsets, and emergency fund for the cash buffer before you quit.
Guide, examples, and methodology
How to use this FIRE calculator
Enter current savings, monthly take-home income, monthly spending, expected investment return, and safe withdrawal rate (often 4% for US planning conversations). The tool estimates your FIRE number (annual spending × 25 when using 4%), years to reach it, and progress over time.
Example (USD)
| Metric | Example | Note |
|---|---|---|
| Monthly spending | $3,500 | Annual need ≈ $42,000 |
| FIRE target (4% rule) | ~$1,050,000 | 25× annual expenses |
| Savings rate | 40% of net income | Often the biggest lever |
How we calculate
We project portfolio growth with monthly contributions implied by income minus expenses, compound at your stated return, and compare to a target based on spending divided by withdrawal rate. The 4% rule is a US retirement research shorthand, not a guarantee—many planners use 3–3.5% for longer retirements or early FIRE.
Common mistakes
- Using gross income instead of after-tax cash flow for savings rate.
- Ignoring health insurance costs before Medicare at 65.
- Assuming flat 10% stock returns every year with no sequence-of-returns risk.
- Forgetting one-time expenses (travel, home repair) in monthly spending.
Related calculators in this topic
- Compound Interest Calculator
- DCA Calculator
- Free Dividend & DRIP Calculator
- Free 401(k) Loan Cost Calculator
Frequently asked questions
What is the 4% rule?
The 4% rule is a planning rule of thumb: withdraw about 4% of your portfolio in year one of retirement, then adjust for inflation. It implies saving roughly 25× your annual expenses. It is based on US historical data and is not a promise of future results.
How much do I need to FIRE?
A common estimate is 25× your annual spending if you use a 4% withdrawal rate. At $50,000/year expenses, that is about $1.25 million invested. Lower spending or a lower withdrawal rate changes the target.
What is the 25× rule for FIRE?
Target portfolio ≈ 25 × annual expenses, based on withdrawing ~4% per year. $48,000/year spending → roughly $1.2M FIRE number. Adjust for your risk tolerance and taxes.
How does savings rate affect years to FIRE?
Higher savings rate = more money invested each month and less spending to cover later. Going from 20% to 50% savings can cut years to FIRE dramatically — often more impactful than chasing an extra 1% return.
What are Lean, Fat, and Coast FIRE?
Lean FIRE: retire on a frugal budget. Fat FIRE: maintain a high lifestyle. Coast FIRE: invest enough early that compounding reaches your later target without further savings — you only need to cover current expenses until traditional retirement.
Is the 4% withdrawal rule still valid?
It is a planning starting point from historical U.S. portfolio data, not a promise. Sequence-of-returns risk, longevity, and healthcare costs can require 3–3.5% in conservative plans. Use our FIRE number as a benchmark, then stress-test lower withdrawal rates.