How the maths works
How to use it
- Enter what your life actually costs each month, all in. This is the number that drives everything else.
- Enter what you have invested and what you add monthly.
- Note the second-order effect: cutting spending lowers the target and raises what you can invest. It moves the date from both directions at once.
A worked example
Spending $3,000 a month is $36,000 a year, so the freedom number is $900,000. Cut spending to $2,800 and the target falls to $840,000 — $60,000 lower — while the spare $200 a month becomes new contributions. A $200 change does not move the goal by $200. It moves it by $60,000 and accelerates the approach.
Where this sits in the Financial Literacy resource
A calculator tells you where you are. It does not tell you what to do next, and a number without a plan behind it tends to produce anxiety rather than progress. These stages are free, need no account, and cover the decision this calculator is measuring.
Common questions
What is the 4% rule?
A planning benchmark from research on historical US portfolio outcomes, suggesting that withdrawing about 4% of an invested balance in the first year — adjusted for inflation after that — had a high historical survival rate over 30 years. Multiplying annual spending by 25 is the same rule inverted. It is a starting estimate, not a guarantee, and it assumes a diversified portfolio and a specific time horizon.
Why is my spending more important than my income?
Because spending sets the target. Every dollar of annual spending adds twenty-five dollars to the amount you need, and every dollar cut removes twenty-five and simultaneously becomes a dollar you can invest. Income raises how fast you approach the number; spending decides where the number sits.
Does this account for Social Security or a pension?
No. It models a portfolio covering your full spending on its own, which is deliberately conservative. Social Security, a pension or any other income stream reduces the amount the portfolio has to carry, and therefore lowers the target.
What this calculator is not
It is an educational model, not a projection and certainly not advice. It knows nothing about your income, your state, your debts or your benefits status, and it ignores taxes and fees unless the page says otherwise. If you receive SSI or SSDI some of this maths works differently and getting it wrong can cost you eligibility — start with the Disability Wealth Guide instead. Our sourcing and correction policy is on the editorial standards page.
Nothing here is stored. Every calculation runs in your browser. No numbers are transmitted, logged or saved to any server, and no account is required. Close the tab and it is gone.