Calculators

11 calculators, each with tested math and a plain-language methodology. Filter by name or keyword.

Home & Mortgage

Mortgages, refinancing, affordability, and rent-vs-buy decisions.

Mortgage Calculator Estimate your full monthly mortgage payment (PITI) including property tax, homeowners insurance, PMI, and HOA, plus total interest and a year-by-year amortization schedule. Refinance Calculator See your new monthly payment, break-even point, and lifetime savings from refinancing, including discount points and the option to roll closing costs into the loan. Home Affordability Calculator Find out how much house you can afford from your income, debts, and down payment, using the standard 28/36 debt-to-income rules and full monthly housing costs. Rent vs Buy Calculator Compare the true total cost of buying versus renting over the years you plan to stay, including transaction costs, equity, appreciation, and the opportunity cost of your down payment.

Retirement & FIRE

Retirement saving, 401(k)s, and financial-independence planning.

401(k) Calculator Project your 401(k) balance at retirement from your contributions, the employer match, expected return, and salary growth, including the match as free money. FIRE Calculator Find your financial independence number and how many years until you reach it, modeled in today's dollars using the 4% rule.

Investing

Compound interest, returns, and long-term investing.

Compound Interest Calculator See how an investment grows from a starting amount plus regular contributions, with an optional yearly contribution increase, and view the result in today's dollars and after tax. Rental Property ROI Calculator Find a long-term rental's cap rate, cash-on-cash return, monthly cash flow, and total return over your holding period, with financing handled correctly. Airbnb ROI Calculator Estimate a short-term rental's cap rate, cash-on-cash return, cash flow, and total return from your nightly rate and occupancy, with the STR-specific expenses handled correctly. Fix and Flip ROI Calculator Estimate a flip's net profit, ROI, cash to close, and your maximum allowable offer with the 70 percent rule, including the points, financing, and holding costs that quietly sink deals.

Loans & Debt

Loan payoff, debt paydown, and interest costs.

HELOC Calculator See how much you can borrow against your home equity at your lender's CLTV cap, plus a home equity line's interest-only draw payment, its much larger repayment payment, and the payment shock between the two phases.