Personal Finance Calculators

Financial independence (FI) means your investments can pay for your life, so work becomes optional. A common rule says you reach it when your portfolio is 25 times what you spend in a year. This shows when you would hit that number, and how much sooner you would get there if you spent less each month. Spending less helps twice: you need a smaller pile, and you save more toward it. Enter household income before taxes. Taxes are estimated for you.

Where you live is the biggest cost in most budgets. This scales your spending by how expensive the new city is compared with the one you live in now. Your income stays the same, as if you keep a remote job. The moving cost comes out of your portfolio up front. Each dot is a real US city, placed by how many years it would take you to reach FI there.

Most plans save all the time off for the end. A sabbatical, a long break from work, takes some of it now and pays for it with a later FI date. During the break you save nothing, and the net cost of the break (what you spend, minus any income) comes out of your portfolio. Afterward you go back to your current income. The striped part of the bar is the time off.

A $15 charge feels small. But each dollar you spend on it is a dollar you can't invest. Invested money grows, and its growth grows too. So the real cost of a subscription is not just what you pay. It is what that money would have turned into if you had invested it instead. Economists call this opportunity cost: the price of the thing you gave up. The receipt shows both parts: what you pay, and the growth you miss. Together they are the real cost, or what you would have if you had never signed up.

Funds charge a fee every year as a share of your whole balance, so the cost grows as your money grows. Both lines start from your current portfolio and add the same amount each month. The only difference is the yearly fee. The shaded gap is the money that goes to the fund company instead of to you.

Enter college costs in today's dollars. They grow 2% a year faster than inflation until your child turns 18. The monthly amount is what you would need to invest, starting now, at your expected return, to cover your share in full by then.

Every extra dollar can pay down debt, which saves you its interest rate for sure. Or it can be invested, which should earn more over time but can lose money. Both paths pay the same each month: a regular payment on the debt (its interest plus 1% of the balance, about what a credit card asks at first) and the extra. In the first path both go to the debt until it is gone, then both are invested. In the second the extra is invested from day one and the regular payment alone pays off the debt, then it is invested too. Loan rates include inflation and your expected return does not, so about 2.5% inflation is added back to the return before the two are compared. Results are in today's dollars.

Refinancing means you pay closing costs now to get a lower rate and a lower monthly payment. The line adds up what you save each month. Once it climbs past the closing costs, you have broken even, and every month after that is money you keep. If you sell, move or refinance again before then, you lose money. Both loans are paid off over the years you have left, so the comparison is fair.

Buying builds equity. It costs a mortgage payment plus about 2% of the home's value a year for taxes, insurance and upkeep, and about 6% when you sell. Renting keeps the down payment and closing costs invested. Each month, whoever pays less invests the difference. Your mortgage payment stays the same while prices rise with inflation (about 2.5% a year), so it gets easier to carry over time. Whichever leaves you with more at the end wins. Results are in today's dollars.

A child is expensive, but the cost comes a little at a time over 18 years while your investments keep growing. This lowers what you save each year by the cost of a child, plus childcare for the first five years, and shows how far that pushes back your FI date.

When one parent stops working, the family loses that paycheck after taxes. But it also stops paying for childcare and work costs like the commute. What is left is the real yearly cost of staying home. It is usually much smaller than the salary.

Three to six months is a common rule. The right amount depends on how likely your income is to stop and how long it would take to replace it. Each item you pick adds months of core spending: the bills you would still have to pay with no income.