calculator
A transparent FIRE number calculator
Turn annual spending and a chosen starting withdrawal rate into a planning target, then see how return and monthly contributions affect a simple accumulation estimate.
- Published
- Sources checked
- By
- FIRE Aggregator editorial process
Estimate a planning target
Formula: annual spending ÷ withdrawal rate = planning target. The projection compounds the current portfolio monthly and adds the selected monthly contribution. It ignores taxes, fees, inflation, and return sequence.
Worked example without JavaScript: $60,000 ÷ 4% = $1,500,000. Change the inputs and select Calculate estimate for a projection.
Start with spending, not a magic multiple
The familiar target is annual portfolio-funded spending divided by a chosen starting withdrawal rate. At 4%, each $1 of annual spending implies $25 of invested assets; $60,000 implies $1.5 million. At 3.5%, the same spending implies about $1.71 million.
Use spending that the portfolio must cover after reliable income such as a pension or Social Security, and keep taxes and health costs visible. The result is a scenario input, not a prediction or a guarantee.
Read the projection as a sensitivity check
The optional projection uses a constant monthly return and end-of-month contributions. Real returns arrive unevenly, fees and taxes reduce results, inflation changes future spending, and a negative early-return sequence can matter greatly after withdrawals begin.
- Recalculate with lower returns, a lower withdrawal rate, and higher spending.
- Compare the result with the SEC calculators rather than treating either tool as individualized advice.
- Revisit Social Security, pension, insurance, and tax assumptions before a decision.
Limits
This deterministic estimate does not model inflation, taxes, fees, asset allocation, Social Security rules, longevity, market volatility, or sequence-of-returns risk. It is an educational scenario tool, not investment advice.
Sources
- SEC Investor.gov Compound Interest Calculator
- SEC Investor.gov Savings Goal Calculator
- Morningstar State of Retirement Income 2025 report
The source-check date records editorial review. Routine builds do not advance it.
Revision history
- — Initial publication after checking the cited SEC and retirement-income research sources.